Question

This isosceles triangle has two sides of equal length, that are longer than the length of the base, b. The perimeter of the triangle is 15.7 centimeters. The equation 2a + b 15.7 models this information If one of the longer sides is 6.3 centimeters, which is used to find the length of the base?

Answer 1

Assuming you're asking what b is:

Substitute and Subtract

$2a + b = 15.7 \\ 2(6.3) + b = 15.7 \\ 12.6 + b = 15.7 \\ b = 3.1$