# What is the error in the proof? (proof in details)

## 100 = 100 10 (10) = (-10)(-10) sqrt((10(10) = sqrt((-10)(-10) 10 = -10

Jul 24, 2018

Below

#### Explanation:

There is an error in the last line

In the third line
$\sqrt{10 \left(10\right)} = \sqrt{- 10 \left(- 10\right)}$

Remember that $\text{negative" times " negative" = "positive}$

Hence, $\sqrt{10 \left(10\right)} = \sqrt{- 10 \left(- 10\right)}$ becomes $\sqrt{10 \left(10\right)} = \sqrt{10 \left(10\right)}$

therefore, your fourth line should say $10 = 10$