Question 1042604
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This 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 can be used to find the side lengths.
If one of the longer sides is 6.3 centimeters, what is the length of the base?
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It is 15.7 - 2*6.3 centimeters.


They just explained you everything. What are your doubts?