Solve sqrt{72}-sqrt{98}*sqrt{8}

$$\sqrt{ 72 } - \sqrt{ 98 } \times \sqrt{ 8 }$$

Evaluate

$$6\sqrt{2}-28\approx -19.514718626$$

Solution Steps

Factor 72=6^{2}\times 2. Rewrite the square root of the product \sqrt{6^{2}\times 2} as the product of square roots \sqrt{6^{2}}\sqrt{2}. Take the square root of 6^{2}.

$$6\sqrt{2}-\sqrt{98}\sqrt{8}$$

Factor 98=7^{2}\times 2. Rewrite the square root of the product \sqrt{7^{2}\times 2} as the product of square roots \sqrt{7^{2}}\sqrt{2}. Take the square root of 7^{2}.

$$6\sqrt{2}-7\sqrt{2}\sqrt{8}$$

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}.

$$6\sqrt{2}-7\sqrt{2}\times 2\sqrt{2}$$

Multiply 7 and 2 to get 14.

$$6\sqrt{2}-14\sqrt{2}\sqrt{2}$$

Multiply \sqrt{2} and \sqrt{2} to get 2.

$$6\sqrt{2}-14\times 2$$

Multiply 14 and 2 to get 28.

$$6\sqrt{2}-28$$