Add or subtract. Assume all variables represent positive real numbers.
-$- 2 \sqrt { 8 } - 2 \sqrt { 18 } - 8 \sqrt { 32 }$
A) $- 12 \sqrt { 2 }$
B) $- 2 \sqrt { 2 }$
C) $- 42 \sqrt { 2 }$
D) $12 \sqrt { 2 }$

Question

Quizplus · Accepted Answer

First, simplify each square root: $\sqrt{8} = 2\sqrt{2}$, $\sqrt{18} = 3\sqrt{2}$, $\sqrt{32} = 4\sqrt{2}$. Substitute back: $-2(2\sqrt{2}) - 2(3\sqrt{2}) - 8(4\sqrt{2}) = -4\sqrt{2} - 6\sqrt{2} - 32\sqrt{2} = -42\sqrt{2}$.

Add or Subtract −28−218−832- 2 \sqrt { 8 } - 2 \sqrt { 18 } - 8 \sqrt { 32 }−28​−218​−832​

Add or Subtract $- 2 \sqrt { 8 } - 2 \sqrt { 18 } - 8 \sqrt { 32 }$