SOLUTION: The area of a trapezoid is 186 in squared. If the height is 11 in. and the longer base is 21 in., what is the length of the shorter base? Round your answer to the nearest tenth.

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Question 109857: The area of a trapezoid is 186 in squared. If the height is 11 in. and the longer base is 21 in., what is the length of the shorter base? Round your answer to the nearest tenth.
Found 2 solutions by BurningFlame_marc, ankor@dixie-net.com:
Answer by BurningFlame_marc(77) (Show Source):
You can put this solution on YOUR website!
Hello!
The formula for the area of a trapezoid is , we know b1 and the height but the problem is we don't know the base2. We can represent b2 as variable x. We know that the area is 186. so the new formula is . First let's distribute 11, if we do that it will be . Then we multiply both sides by 2 so there is no fraction, it will be like this we got 372 because we multiply 186 by 2, we got 231+11x because we multiply 231+11x/2 by 2. Is that clear? Now, we got this equation let's subtract 231 from 372 and 231+11x. We will get divide both sides by 11. You will get . So the final answer is 12.82in.

I hoped you understand my solution!

Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
The area of a trapezoid is 186 in squared. If the height is 11 in. and the longer base is 21 in., what is the length of the shorter base? Round your answer to the nearest tenth.
:
The formula
A = *h*(a+b)
:
Solve for a (the shorter side)
:
Mult equation by 2 to get rid of the fraction:
h(a+b) = 2A
:
Divide both sides by h:
a + b =
:
Subtract b from both sides
a = - b
:
Substitute the given values in the above equation:
a = - 21
:
a = - 21
:
a = 33.8 - 21
:
a = 12.8 is the shorter side
:
:
Check solution:
A = *11(12.8+21)
A = *11(33.8)
A = *371.8
A = 185.9 ~ 186