Question

5x^2-40=0; solve by using square roots.

Answer 1

5x- SR 40= 0., add to the other side, 5x= SR 40. divide both sides by 5, x= SR of 8, or 2 SR 2

Answer 2

5x²-40=0. Add 40 to both sides. 5x²=40. Square both sides of the equation, use add or subtract sign. 5x=+-$\sqrt{40}$. Then simplify the radical and divide both sides by 5. The answer is 2$\sqrt{2}$ or -2$\sqrt{2}$