<PRE><B>Question 1076945</B>
let s be the length of one side of the equilateral triangle
:
a)  3s + 7 = 40
s = (40 - 7) / 3
:
b)  s = 33 / 3 = 11
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the length of a side of the equilateral triangle is 11 cm
check answer
:
3 * 11 + 7 = 40
:
33 + 7 = 40
:
40 = 40
:
answer checks
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