SOLUTION: One leg of an isosceles triangle has a length of (x2 + 9)cm. The base of the isosceles triangle has a length of (5x + 12)cm. The perimeter of the triangle is 42 cm. Find the val

Question 246855: One leg of an isosceles triangle has a length of (x2 + 9)cm. The base of the isosceles triangle has a length of (5x + 12)cm. The perimeter of the triangle is 42 cm. Find the value(s) for x and the lengths of the sides.
Answer by solver91311(24713) (Show Source): You can put this solution on YOUR website!

If it is an isosceles triangle, then the two legs have to be equal. So:

Collect like terms, put the quadratic in standard form, and solve. The quadratic factors. One of the roots will be negative, so discard it -- a negative measure for the side of a triangle is absurd. Substitute the positive root in the expressions for your triangle sides and do the arithmetic.

John

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