1.
What constant term must be added to a-14a+___= 0 to make it a perfect square trinomial?
Correct Answer
C. 49
Explanation
To make the given trinomial a perfect square, we need to find the square of half the coefficient of the 'a' term. In this case, half of -14a is -7a. The square of -7a is 49a^2. Therefore, we need to add 49a^2 to the trinomial to make it a perfect square. Since there is no variable term in the trinomial, we can simply say that we need to add 49 to make it a perfect square trinomial.
2.
Where is the vertex of the parabola f(x)=3(x-1)^2 +4?
Correct Answer
B. (1,4)
Explanation
The vertex of a parabola in the form f(x) = a(x-h)^2 + k is located at the point (h, k). In this case, the equation is f(x) = 3(x-1)^2 +4, so the vertex is at (1, 4).
3.
Which parabola does not have its axis of symmetry on the y-axis?
Correct Answer
D. Y=(x-2)^2
Explanation
The equation y=(x-2)^2 represents a parabola that has its axis of symmetry shifted 2 units to the right of the y-axis. This can be determined by the presence of the term (x-2) in the equation, which indicates that the vertex of the parabola is located at x=2. Since the vertex is not on the y-axis, this parabola does not have its axis of symmetry on the y-axis.
4.
What quadratic function has a maximum point?
Correct Answer
A. F(x)=-x^2+3
Explanation
The quadratic function f(x)=-x^2+3 has a maximum point because the coefficient of x^2 is negative. When the coefficient of x^2 is negative, the graph of the quadratic opens downwards, creating a concave shape. In this case, the maximum point occurs at the vertex of the parabola, which is the highest point on the graph. Therefore, f(x)=-x^2+3 has a maximum point.
5.
Which of the following is NOT a perfect square trinomial?
Correct Answer
B. Y^2+8y+7
Explanation
The given trinomial y^2+8y+7 is not a perfect square trinomial because it cannot be factored into two identical binomials. In a perfect square trinomial, the first and last terms are perfect squares, and the middle term is twice the product of the square root of the first term and the square root of the last term. However, in y^2+8y+7, the first and last terms (y^2 and 7) are not perfect squares, and the middle term (8y) does not meet the criteria for a perfect square trinomial.
6.
Find the product of (6x-3) and (x+5).
Correct Answer
D. 6x^2+27x-15
Explanation
To find the product of (6x-3) and (x+5), we can use the distributive property. We multiply each term in the first expression (6x-3) by each term in the second expression (x+5).
(6x * x) + (6x * 5) + (-3 * x) + (-3 * 5)
= 6x^2 + 30x - 3x - 15
= 6x^2 + 27x - 15
Therefore, the correct answer is 6x^2 + 27x - 15.
7.
Which of the following equations of a parabola has the widest graph?
Correct Answer
D. Y=1/4x^2
Explanation
The equation y=1/4x^2 represents a parabola with a coefficient of 1/4 in front of the x^2 term. The coefficient determines the width of the parabola, with a smaller coefficient resulting in a wider graph. Since 1/4 is the smallest coefficient among the given options, the equation y=1/4x^2 has the widest graph.
8.
Factor x^2-64.
Correct Answer
C. (x+8)(x-8)
Explanation
The given expression is a quadratic trinomial in the form of x^2 - 64. This can be factored using the difference of squares formula, which states that a^2 - b^2 can be factored as (a + b)(a - b). In this case, a = x and b = 8. Therefore, the factored form of the expression is (x + 8)(x - 8).
9.
What is the axis of symmetry of f(x)=(x+1)^2+1?
Correct Answer
C. X=-1
Explanation
The axis of symmetry of a quadratic function is a vertical line that passes through the vertex of the parabola. In this case, the function is in the form f(x) = (x+1)^2 + 1, which represents a parabola that opens upwards. The vertex of the parabola is at (-1, 1), which means the axis of symmetry is a vertical line passing through x = -1. Therefore, the correct answer is x = -1.
10.
Which of the following is equal to (x+2)(x+2) or (x+2)^2?
Correct Answer
B. X^2+4x+4
Explanation
The given expression (x+2)(x+2) or (x+2)^2 represents the square of the binomial (x+2). To find the product, we use the FOIL method, which stands for First, Outer, Inner, Last. When we apply the FOIL method, we multiply the first terms of both binomials (x and x), the outer terms (x and 2), the inner terms (2 and x), and the last terms (2 and 2). Simplifying these products, we get x^2+4x+4, which is the correct answer.
11.
Which of the following quadratic functions has the narrowest graph?
Correct Answer
C. F(x)=4x^2
Explanation
The quadratic function f(x)=4x^2 has the narrowest graph because the coefficient of x^2 is the largest among all the given options. The coefficient of x^2 determines the steepness of the graph. A larger coefficient results in a steeper graph, while a smaller coefficient results in a wider graph. Therefore, f(x)=4x^2 has the narrowest graph compared to the other options.
12.
What is the turning point of the parabola?
Correct Answer
A. Vertex
Explanation
The turning point of a parabola is the vertex. The vertex is the point on the parabola where it changes direction from upward to downward or vice versa. It is the highest or lowest point on the graph of the parabola, depending on whether the parabola opens upward or downward. The vertex is also the point where the parabola intersects the line of symmetry, which is a vertical line that divides the parabola into two symmetrical halves. Therefore, the vertex is the correct answer.
13.
Which of the following trinomials is a perfect square trinomial?
Correct Answer
B. X^2-8x+16
Explanation
The trinomial x^2-8x+16 is a perfect square trinomial because it can be factored into (x-4)(x-4), which is equivalent to (x-4)^2. This shows that it is the square of a binomial, making it a perfect square trinomial.
14.
Which of the following quadratic functions has the vertex at the origin?
Correct Answer
A. F(x)=4x^2
Explanation
The quadratic function f(x)=4x^2 has the vertex at the origin because the vertex of a quadratic function in the form f(x)=ax^2+bx+c is given by (-b/2a, f(-b/2a)). In this case, a=4, b=0, and c=0. Therefore, the x-coordinate of the vertex is -b/2a = 0, and the y-coordinate is f(0) = 0. Hence, the vertex is at the origin (0,0).
15.
What is the quadratic function with zeros 2 and -3?
Correct Answer
A. F(x)=x^2+x-6
Explanation
The quadratic function with zeros 2 and -3 can be found using the fact that the zeros of a quadratic function are the values of x for which the function equals zero. In this case, the zeros are 2 and -3. To find the quadratic function, we can use the factored form of a quadratic equation, which is (x - r1)(x - r2) = 0, where r1 and r2 are the zeros. Plugging in the given zeros, we get (x - 2)(x + 3) = 0. Expanding this equation gives us x^2 + x - 6, which matches the first option, f(x) = x^2 + x - 6.
16.
Which function is not quadratic?
Correct Answer
B. F(x)=x-2
Explanation
The function f(x) = x-2 is not quadratic because it does not have a squared term. In a quadratic function, the highest power of the variable should be 2. In this case, the highest power of x is 1, so it is a linear function.
17.
What are the roots of x^2-5x-6=0?
Correct Answer
A. 6 and -1
Explanation
The given quadratic equation is in the form of ax^2 + bx + c = 0. By applying the quadratic formula, x = (-b Â± âˆš(b^2 - 4ac)) / 2a, we can find the roots. In this case, a = 1, b = -5, and c = -6. Plugging these values into the quadratic formula, we get x = (5 Â± âˆš(25 + 24)) / 2. Simplifying further, we have x = (5 Â± âˆš49) / 2. This gives us two possible solutions: x = (5 + 7) / 2 = 6 and x = (5 - 7) / 2 = -1. Therefore, the roots of the equation are 6 and -1.
18.
Find the solution set of the equation x^2+6x-7.
Correct Answer
B. 1,-7
Explanation
The solution set of the equation x^2+6x-7 is 1 and -7. This can be found by factoring the equation as (x+7)(x-1) = 0 and setting each factor equal to 0 to solve for x. Therefore, x = 1 and x = -7 are the values that satisfy the equation.
19.
The nature of roots of 3x^2+5x+1=0
Correct Answer
D. Real,unequal,irrational
Explanation
The given quadratic equation 3x^2+5x+1=0 has real roots because the discriminant (b^2-4ac) is positive. Since the discriminant is positive and not a perfect square, the roots are irrational. Additionally, the roots are unequal because the quadratic equation does not have a perfect square trinomial form. Therefore, the nature of the roots of the given equation is real, unequal, and irrational.
20.
What is the equation of the quadratic function whose graph is congruent to the graph of f(x)=x^2 with vertex at (0,3)?
Correct Answer
A. F(x)=x^2+3
Explanation
The equation of a quadratic function with a vertex at (0,3) can be written in the form f(x) = a(x-h)^2 + k, where (h,k) represents the vertex. In this case, h=0 and k=3. Plugging in these values, we get f(x) = a(x-0)^2 + 3, which simplifies to f(x) = ax^2 + 3. Since there are no other terms in the equation, the correct answer is f(x) = x^2 + 3.
21.
The vertex is the minimum point when the parabola opens downward.
Correct Answer
B. False
Explanation
When a parabola opens downward, the vertex is actually the maximum point, not the minimum point. The vertex is the point where the parabola reaches its highest or lowest point, depending on whether it opens upward or downward. Therefore, the given statement is incorrect.
22.
The polynomial of degree 2 is called square root function.
Correct Answer
B. False
Explanation
The given statement is false. A polynomial of degree 2 is not called a square root function. A square root function is a type of function that involves finding the square root of a number. A polynomial of degree 2 is a quadratic function, which can be written in the form of ax^2 + bx + c, where a, b, and c are constants.
23.
The vertex is the maximum point when the parabola opens upward.
Correct Answer
B. False
Explanation
When a parabola opens upward, the vertex is the minimum point, not the maximum point. The vertex is the point where the parabola reaches its highest or lowest point depending on the direction it opens. Therefore, the correct answer is False.
24.
The line of symmetry acts as a mirror which divides the parabola into two symmetrical parts.
Correct Answer
A. True
Explanation
The statement is true because a parabola has a line of symmetry that divides it into two symmetrical parts. This line of symmetry acts as a mirror, reflecting one side of the parabola onto the other side. This property of a parabola can be observed by folding a piece of paper along the line of symmetry, where the two halves will perfectly overlap each other.
25.
The vertex of the quadratic function f(x)=ax^2 is at the origin.
Correct Answer
A. True
Explanation
The statement is true because the vertex of a quadratic function in the form f(x) = ax^2 is always at the origin (0,0). This is because the vertex is the point on the graph where the function reaches its minimum or maximum value, and for a quadratic function, the minimum or maximum value is always at the vertex. Since the coefficient of x^2 is a, the function is symmetric about the y-axis, and the vertex is located at the origin.