Shape Variables: Solve Area & Perimeter Problems

A triangle has a base of x cm and a height of 5 cm. If the area of the triangle is 30 cm², what is the value of x?

• 10

• 15

• 12

• 8

A rectangle has a length of 2x meters and a width of 3 meters. If the perimeter of the rectangle is 20 meters, what is the value of x?

• 3.5

• 2

• 4

• 5.5

A circle has a radius of x inches. If the circumference of the circle is 31.4 inches, what is the value of x? (Use π = 3.14)

• 6

• 4

• 7

• 5

A square has a side length of x feet. If the area of the square is 64 square feet, what is the value of x?

• 8 feet

• 10 feet

• 6 feet

• 4 feet

A trapezoid has bases of x cm and 6 cm, and a height of 4 cm. If the area of the trapezoid is 40 cm², what is the value of x?

• 14

• 16

• 12

• 10

A parallelogram has a base of 3x meters and a height of 4 meters. If the area of the parallelogram is 48 square meters, what is the value of x?

• 4

• 5

• 2

• 6

A right triangle has legs of lengths x cm and 4 cm. If the hypotenuse is 5 cm, what is the value of x?

• 6

• 2

• 3

• 4

A rectangle has a length of 5 cm and a width of x cm. If the area of the rectangle is 45 cm², what is the value of x?

• 12 cm

• 10 cm

• 7 cm

• 9 cm

A hexagon has a perimeter of 36 cm. If each side is x cm long, what is the value of x?

• 5 cm

• 6 cm

• 8 cm

• 7 cm

A circle has a diameter of x cm. If the area of the circle is 78.5 cm², what is the value of x? (Use π = 3.14)

• 8 cm

• 12 cm

• 15 cm

• 10 cm