Solve sqrt{18}-3sqrt{8}

$$\sqrt { 18 } - 3 \sqrt { 8 }$$

Evaluate

$$-3\sqrt{2}\approx -4.242640687$$

Solution Steps

Factor 18=3^{2}\times 2. Rewrite the square root of the product \sqrt{3^{2}\times 2} as the product of square roots \sqrt{3^{2}}\sqrt{2}. Take the square root of 3^{2}.

$$3\sqrt{2}-3\sqrt{8}$$

Factor 8=2^{2}\times 2. Rewrite the square root of the product \sqrt{2^{2}\times 2} as the product of square roots \sqrt{2^{2}}\sqrt{2}. Take the square root of 2^{2}.

$$3\sqrt{2}-3\times 2\sqrt{2}$$

Multiply -3 and 2 to get -6.

$$3\sqrt{2}-6\sqrt{2}$$

Combine 3\sqrt{2} and -6\sqrt{2} to get -3\sqrt{2}.

$$-3\sqrt{2}$$