Answer:
The answer is 15cm
Step-by-step explanation:
Let b be the length of the second parallel side
Area of a trapezium is given by
[tex]A = \frac{1}{2} (a + b)h[/tex]
where
h is the height
a and b are the parallel sides
From the question
Area = 230 cm²
height = 20cm
one of parallel side / a = 8 cm
Substitute the values into the above formula and solve for b
That's
[tex]230 = \frac{1}{2} ( 8 + b) 20[/tex]
Reduce the fraction with 2
That's
[tex]230 = (8 + b) \times 10[/tex]
Expand the terms
That's
[tex]230 = 80 + 10b[/tex]
[tex]10b = 230 - 80 \\ 10b = 150[/tex]
Divide both sides by 10
We have the final answer as
b = 15cm
Hope this helps you
