Question

28 points !!!! help

Q4. The area of a trapezium is 45 cm2

and the perpendicular distance
between its parallel sides is 5 cm. If the length of one of its parallel sides is
6cm, find the length of the other parallel side.

Answer 1

12 cm

Explanation:

45 = ½ (6 + x) × 5

18 = 6 + x

x = 12

Answer 2

12 cm

Explanation:

The area (A) of a trapezium is calculated as

A =
`(1)/(2)` h (a + b)

where h is the perpendicular height and a, b the parallel bases.

Here A = 45, h = 5, a = 6 and b = ?, thus

45 =
`(1)/(2)` × 5 × (6 + b) = 2.5(6 + b) = 15 + 2.5b ( subtract 15 from both sides )

30 = 2.5b ( divide both sides by 2.5 )

b = 12

The measure of the other parallel side is 12 cm