Question

Given: ABCD is a trapezoid, AD = 10, BC = 8, Area of ∆ACD = 30. Find: Area of ABCD

Answer 1

Just multiply them.
10 times 8 equals 80.
Area=80

Answer 2

Answer:

$\text{The area of trapezoid ABCD is }54 units^2$

Step-by-step explanation:

Given that ABCD is a trapezoid, AD = 10, BC = 8 and the area of ∆ACD = 30.

we have to find the area of trapezoid ABCD.

$\text{Area of triangle ACD}=\frac{1}{2}\times base\times height$

$30=\frac{1}{2}\times 10\times h$

$h=\frac{30\times 2}{10}=6 units$

The area of trapezoid can be calculated by the formula

$=\frac{1}{2}\times (\text{sum of parallel sides})\times height$

$=\frac{1}{2}\times (AD+BC)\times h$

$=\frac{1}{2}\times (10+8)\times 6$

$=\frac{1}{2}\times 18\times 6=54 units^2$

$\text{Hence, the area of trapezoid ABCD is }54 units^2$