Find the difference: square root20 - square root80

-2√ (5)

Step-by-step explanation:

√ (20) = √ (4*5) = √ (4) * √ (5) = 2*√ (5) = 2√ (5)

√ (80) = √ (16*5) = √ (16) * √ (5) = 4*√ (5) = 4√ (5)

therefore : √ (20) - √ (80) = 2√ (5) - 4√ (5) = (2 - 4) * √ (5) = - 2√ (5)