Question

The isosceles triangle has a perimeter of 7.5 m Which equation can be used to find the value of x if the shortest side, y, measures 2.1 m?

Answer 1

P = 2*side + 2.1 = 7.5
2*side = 5.4
side = 2.7 m

Answer 2

we know that

In an isosceles triangle, the two equal sides are called legs, and the remaining side is called the base

so

In this problem

Let

x---------> the length side of the legs

y---------> the length side of the base

Perimeter of the triangle is equal to

$P=2x+y\\ P= 7.5 m\\ y=2.1 m$

substitute the values and solve for x

$7.5= 2x+2.1\\ 2x= 7.5-2.1\\ 2x=5.4\\\\ x=\frac{5.4}{2} \\\\ x=2.7\ m$

therefore

the answer is

The equation that can be used to find the value of x is

$7.5= 2x+2.1$

The value of x is $2.7\ m$