# Math

Given A=(1/2)(h)(a+b) Find:

a. A if h=25, a=15, b=42

b. h if A=260, a=8, b=5

c. a if A=322, h=14, b=15

d. b if A=448, h=16, a=25

This makes no sense to me whatsoever. Please clarify as to what I'm supposed to do?
Thank you very much!

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1. I recognize the formula for the area of a trapezoid where a and b are the two parallel sides and h is the height between them, so just plug in the values.

I will do the first

a. A = (1/2)(25)(15+42)
= (1/2)(25)(57) = 1425/2 or 712.5 square units

do the others the same way, except you are given different combinations

d. 448 = (1/2)(16)(25+b)
448 = 8(25+b)
56 = 25 + b
b = 31

etc

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2. 👎

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