When is it not appropriate to use decimals and percentages?

If f(x)=x^3 and g(x)=2x+7 when g(x)=-5

Prove the converse of the pythagorean theorem using similar triangles. the converse of the pythagorean theorem states that when the sum of the squares of the lengths of the legs of the triangle equals the squares length of the hypotenuse, the triangle is a right triangle. be sure to create and name the appropriate geometric figures.

What should be done to both sides of the equation in order to solve -5m = -40? a) multiply by -5. b) divide by -5. c) multiply by -40. d) divide by -40.