Use a known formula to solve.

Question

A triangular sign in a window has a perimeter of 13.5 ft. Two sides of the triangle are the same length while the third side is 3 foot longer than those sides. Find the lengths of the sides of the sign.

Answer 1

let the two sides of equal length be represented by x

the 3rd side can be represented by (x + 3)

the perimeter of the triangle is the sum of the length of the three sides

 

x + x + (x + 3) = 13.5

 

3x + 3 = 13.5

 

3x = 10.5

 

x = 3.5 ft

 

The two sides of equal length are each 3.5 ft long. The third side has a length of 3.5 + 3 = 6.5 ft.

Answer 2

Here are your sides:

 

x, x, and x + 3.

 

 

Your equation to solve is

 

x + x + x + 3 = 13.5

 

 

Solve for x.