Question

The length of the base of an isosceles triangle is x. The length of a leg is 3x-5. The perimeter of the triangle is 39. Find X.

Answer 1

x = 7

Explanation:

In an isosceles triangle, both legs are always congruent. The length of one leg is given, and the other leg has to be the same. The perimeter of this triangle can be written as:

`x+(3x-5)+(3x-5)=39`

With this equation, all you need to do is solve for x.

`3+3x-5+3x-5=39\\(-5-5)+(x+3x+3x)=39\\-10+7x=39\\7x=49\\x=7`