Chapter 9 - Roots and Radicals - 9.5 - Solving Radical Equations - Problem Set 9.5 - Page 424: 8

x=16/5

Recall, in order to cancel out a square root, we square both sides of the equation. Thus, we square both sides of the equation to obtain that 5x=16. We divide both sides of the equation by 5 to isolate x and obtain: x=16/5. We now must check our solution: $\sqrt{16/5 \times 5} = 4 \\\\\ \sqrt {16}=4 \\\\ 4=4$ This is true, so x=16/5