Hi
First dont panic. this one is pretty easy.
you known that the perimeter is the addition of every sides of a figure.
you have the total perimeter : 84.6
so now you just have to withdraw every side you have to the total , and the missing measure will be the result.
have a try ! you can make it.
<h3>Answer</h3>
First multiply everything by 27

Then approximate the terms with 27 if it's possible (27 and 9) (27 and 27)

So now multiply again

And you have


You're welcome if it's right
Solve for y
minus 10x from both sides
5y<-10x+15
divide both sides by 5
y<-2x+3
6.75 is the answer to your question