Question

Please answer this with steps

Answer 1

Answer:

(y² - 4y - 8)

Step-by-step explanation:

Let's name the sides of the triangle A, B, C.

Perimeter of the triangle = a + b + c = (3y² - 5y) + (4y² + 12) + c = (8y² - 9y + 4)

Using algebra we can find C -

c = (8y² - 9y + 4) - (3y² - 5y) - (4y² + 12)

= 8y² - 9y + 4 - 3y² + 5y - 4y² - 12

= 8y² - 3y² - 4y² - 9y + 5y + 4 - 12

= (y² - 4y - 8)

Answer 2

Answer:

The Third side is (y²-4y-8)

Step-by-step explanation:

Let the third side be X.

(3y²-5y) +(4y²+12) + X= 8y²-9y+4

(7y²- 5y+12) +X= 8y²-9y+4

X = (8y²-9y+4) - (7y²- 5y+12)

X = 8y²-9y+4 - 7y²+5y-12

X= y²-4y-8

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