Question

Side lengths of a triangle 5x-1 and 4x+1

Answer 1

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If your triangle is a right triangle AND 5x-1 and 4x+1 represent the lengths of the 2 shortest sides, then the Pyth. Theorem tells us that

(5x-1)^2 + (4x+1)^2 = (hypotenuse length)^2.

We know that this could not be an equilateral triangle, because 5x-1 differs from 4x+1.

This could be an isosceles triangle if the third side were either 5x-1 or 4x+1.

Please be more specific about what you're supposed to do here.