9th Grade Math Formulas Quiz

1. What is the formula for the area of a square?

A=s2

A=s

A=s3

A=s + s

The formula for the area of a square is A=s2. This formula is derived from the fact that a square has all sides equal in length. To calculate the area, we simply multiply the length of one side (s) by itself (s2). This gives us the total area enclosed by the square.

Explanation

The formula for the area of a square is A=s2. This formula is derived from the fact that a square has all sides equal in length. To calculate the area, we simply multiply the length of one side (s) by itself (s2). This gives us the total area enclosed by the square.

2. What is the formula for the area of the rectangle?

A= L + W

A= W2

A= L2

A= L × W

The formula for the area of a rectangle is A = L × W, where A represents the area, L represents the length, and W represents the width. This formula is derived from the concept that the area of a rectangle is equal to the product of its length and width. Therefore, to find the area of a rectangle, you multiply the length by the width.

Explanation

The formula for the area of a rectangle is A = L × W, where A represents the area, L represents the length, and W represents the width. This formula is derived from the concept that the area of a rectangle is equal to the product of its length and width. Therefore, to find the area of a rectangle, you multiply the length by the width.

3. C=2πr is the formula for

Circumference of a Triangle

Area of a Circle

Circumference of a Circle

None of these

The formula C=2πr represents the circumference of a circle. The circumference is the distance around the outer edge of a circle. The formula states that the circumference is equal to 2 times pi (approximately 3.14) times the radius of the circle. This formula is commonly used to calculate the length of the boundary of a circle.

Explanation

The formula C=2πr represents the circumference of a circle. The circumference is the distance around the outer edge of a circle. The formula states that the circumference is equal to 2 times pi (approximately 3.14) times the radius of the circle. This formula is commonly used to calculate the length of the boundary of a circle.

4. 2 × (L+W) is the formula for

The perimeter of a triangle

The perimeter of a rectangle

The perimeter of a pentagon

The area of a pentagon

The formula 2 × (L+W) is used to calculate the perimeter of a rectangle. The perimeter of a rectangle is the sum of all its sides, which is calculated by adding twice the length (L) and twice the width (W) of the rectangle. Therefore, the correct answer is the perimeter of a rectangle.

Explanation

The formula 2 × (L+W) is used to calculate the perimeter of a rectangle. The perimeter of a rectangle is the sum of all its sides, which is calculated by adding twice the length (L) and twice the width (W) of the rectangle. Therefore, the correct answer is the perimeter of a rectangle.

5. What is the formula for the perimeter of a square?

P = 2s

P = 3s

P = 4s

P = 8s

The formula for the perimeter of a square is P = 4s, where P represents the perimeter and s represents the length of one side of the square. This formula is derived from the fact that a square has four equal sides, so to calculate the perimeter, we multiply the length of one side by 4.

Explanation

The formula for the perimeter of a square is P = 4s, where P represents the perimeter and s represents the length of one side of the square. This formula is derived from the fact that a square has four equal sides, so to calculate the perimeter, we multiply the length of one side by 4.

6. The area of a Triangle is

B+H

BxHx2

BH/2

B/H

The correct answer is BH/2. This is because the formula for finding the area of a triangle is base times height divided by 2. In this case, the base is represented by B and the height is represented by H. By multiplying B and H and then dividing the result by 2, we can find the area of the triangle.

Explanation

The correct answer is BH/2. This is because the formula for finding the area of a triangle is base times height divided by 2. In this case, the base is represented by B and the height is represented by H. By multiplying B and H and then dividing the result by 2, we can find the area of the triangle.

7. Cosec θ =

1/sin θ

1+sin θ

1/sec θ

2/sin θ

The cosecant of an angle θ is equal to 1 divided by the sine of θ. This can be derived from the reciprocal identity of sine, which states that the reciprocal of sine is equal to the cosecant. Therefore, the correct answer is 1/sin θ.

Explanation

The cosecant of an angle θ is equal to 1 divided by the sine of θ. This can be derived from the reciprocal identity of sine, which states that the reciprocal of sine is equal to the cosecant. Therefore, the correct answer is 1/sin θ.

8. Cos θ is equal to

1/sec θ

1/sin θ

1/cosec θ

1/sin x sec θ

The correct answer is 1/sec θ because the reciprocal of the secant function is equal to the cosine function. Therefore, 1/sec θ is equivalent to cos θ.

Explanation

The correct answer is 1/sec θ because the reciprocal of the secant function is equal to the cosine function. Therefore, 1/sec θ is equivalent to cos θ.

9. What is the area of a sphere?

2πr2

4πr2

4πr

4πr3

The formula for the surface area of a sphere is given by 4πr^2, where r is the radius of the sphere. This formula calculates the total area covered by the surface of the sphere. Therefore, the correct answer is 4πr^2.

Explanation

The formula for the surface area of a sphere is given by 4πr^2, where r is the radius of the sphere. This formula calculates the total area covered by the surface of the sphere. Therefore, the correct answer is 4πr^2.

10. The formula for the cotangent is

Cotθ = opposite/hypotenuse

Cotθ = opposite/adjacent

Cotθ = adjacent x opposite

Cotθ = adjacent/opposite

The given formula for the cotangent is Cotθ = adjacent/opposite. This formula represents the ratio of the length of the adjacent side to the length of the opposite side in a right triangle. The cotangent is a trigonometric function that helps determine the angle's measure based on the lengths of the sides of a triangle. By dividing the length of the adjacent side by the length of the opposite side, we can find the cotangent of the angle.

Explanation

The given formula for the cotangent is Cotθ = adjacent/opposite. This formula represents the ratio of the length of the adjacent side to the length of the opposite side in a right triangle. The cotangent is a trigonometric function that helps determine the angle's measure based on the lengths of the sides of a triangle. By dividing the length of the adjacent side by the length of the opposite side, we can find the cotangent of the angle.