Question

A triangle has a perimeter of 7x-2y+15 and has sides of length 5x+y and 7+x , what is the length of the third side?

Answer 1

Answer : Third side will be x-3y+8 .

Explanation :

We have given that,

Length of first side of triangle = 5x+y

Length of second side of triangle = 7+x

Perimeter of triangle = 7x-2y+15

Now , we know that " Perimeter means sum of boundary",

So,

`Perimeter = 5x+y+7+x+\text{ third side}\\7x-2y+15=5x+y+7+x+\text{third side}\\7x-2y+15-5x-y-7-x=\text{third side}\\x-3y+8 = \text{third side}`

So, Length of third side will be x-3y+8.