Answer:
This assumes that the question was meant to read:
"A triangle has side lengths of (7x−4) centimeters, (x+3) centimeters, and (3x+2) centimeters." And not "A triangle has side lengths of (7x-4)(7x−4) centimeters, (x+3)(x+3) centimeters, and (3y+2)(3y+2) centimeters."
If the revision is correct, the perimeter is 11x + 1 cm
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If the question was correctly written, then answer is:
50x^2 - 50x + 9y^2 + 12 y + 29
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Step-by-step explanation:
(7x-4) cm
+ (x+3) cm
+ (3x+2) cm
11x + 1 cm
If the question was correctly written as is, then:
(7x-4)(7x−4) = 49x^2 - 56x + 16
+(x+3)(x+3) = + x^2 + 6x + 9
+(3y+2)(3y+2) = +9y^2 + 12 y + 4
50x^2 - 50x + 9y^2 + 12 y + 29 cm