Question

The isosceles triangle has two sides of equal length , a , 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 equation can be used to find the length of the base ?

Answer 1

Explanation:

Since the length of one of the longer sides, a, has been given to be 6.3, plug it into the equation.

2(6.3) + b = 15.7

12.6 + b = 15.7

b = 15.7 - 12.6

b = 3.1

Answer 2

Equation that can be used to find length of the base is b + 12.6 = 15.7 and the length of the base we get from this equation is 3.1 cm

Explanation:

Given:

Length of the equal side of the Isosceles Triangle = a

Length of the base of the triangle = b

Equal sides are longer than base of the triangle.

Perimeter of the triangle = 15.7 cm

Equation representing given information = 2a + b = 15.7

To find: Equation that represent or can be used to find length of the base if longer side = 6.3 cm

Given Equation is the Equation representing the perimeter of the isosceles triangle.

Longer side = 6.3 cm = Length of the Equal Sides of the triangle.

So, a = 6.3 cm

Now,

2 × 6.3 + b = 15.7

b + 12.6 = 15.7

b = 15.7 - 12.6

b = 3.1 cm

Therefore, Equation that can be used to find length of the base is b + 12.6 = 15.7 and the length of the base we get from this equation is 3.1 cm