Question

The area of a trapezoid is 243cm2. The height is 18cm and the length of one of the parallel sides is 10cm. Find the length of the second parallel side. Express your answer as a simplified fraction or a decimal rounded to two places.

Answer 1

Answer:

$Side_2 = 17\ cm$

Step-by-step explanation:

Given

Shape: Trapezoid

$Area = 243cm^2$

$Height = 18cm$

$Side_1 = 10cm$

Required

Determine the length of the second parallel side

The area of a trapezoid is:

$Area = \frac{1}{2}(Side_1 + Side_2) * Height$

Substitute values for Area, Height and Side1

$243 = \frac{1}{2}(10 + Side_2) * 18$

Multiply both sides by 2

$2 * 243 = 2 * \frac{1}{2}(10 + Side_2) * 18$

$486 = (10 + Side_2) * 18$

Divide both sides by 18

$27 = 10 + Side_2$

$Side_2 = 27 - 10$

$Side_2 = 17\ cm$

Hence;

The length of the second parallel side is 17cm