Let the length of the third side be x inches.
We are given that the perimeter of the triangle is 21 in, so we can set up the equation:
x + (sum of the other two sides) = 21
x + 15 = 21
Subtracting 15 from both sides, we have:
x = 6
Therefore, the length of the third side is 6 inches.
Find the length of the third side of a triangle with a perimeter of 21 in. if the sum of the other two is 15 in.
Set up and equation and solve
1 answer
1 answer