Question

The isosceles triangle has a perimeter of 7.5m. Which equation can be used to find the value of X if the shortest side,y, measures 2.1m? A. 2x-2.1=7.5 B. 4.2+y=7.5 C. y-4.2=7.5 D. 2.1+2x=7.5

Answer 1

I tried this:

Explanation:

I think that `x` would be the length of one of the two equal sides:

We know that the perimeter `P` will be the sum of the lengths of the sides:

`P=x+x+y`

rearrange:

`2x-y=P`

with your values:

`2x-2.1=7.5`