Let the perimeter = base + base + height + height.
Let base = b; height = h; Perimeter = p
Simplify.
p = 2(b) + 2(h)
Perimeter =72, height = 14
72 = 2(b) + 2(14)
Simplify
72 = 2(b) + 28
Isolate the b. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS.
Subtract 28 from both sides
72 (-28) = 2b + 28 (-28)
72 - 28 = 2b
44 = 2b
Isolate the b. Divide 2 from both sides
(44)/2 = (2b)/2
b = 44/2
b = 22
22 centimeters is your answer
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