Answer:
Step-by-step explanation:
(a) Let x represent the length of the first side. Then the second side is (x+4) and the third side is (x+3). The perimeter is ...
x + (x+4) +(x+3) = 15
3x = 8 . . . . collect terms, subtract 7
x = 2 2/3 . . . . divide by 3
The third side is x+3 = 5 2/3 inches.
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(b) For this, we are told the second side is S, so we have ...
S = (x+4)
x = S -4 . . . . . subtract 4 to solve for x
Using this in our expression (in part (a)) for the third side, we have ...
third side = (x +3) = (S -4) +3
third side = S -1
