Question

Combine and simplify these radicals. square root of 8 times square root of 20

Answer 1

√8 * √20 = 4√10

Explanation:

√8 * √20= √(4*2) * √(4*5)

√8 * √20 = (√4)(√2)*(√4)(√5)

√8 * √20 = (2)(√2)*(2)(√5)

√8 *√20 = (2*2)(√2*√5)

√8 * √20 = (4)(√(2*5)

√8 * √20 = 4√10

Answer 2

sqrt(8) = sqrt(2 * 2 * 2) = 2 sqrt(2)
sqrt(20) = sqrt(2 * 2 * 5) = 2 sqrt(5)
Now multiply
2*sqrt(2) * 2 sqrt(5)
= 2 * 2 * sqrt(2) * sqrt(5)
= 4 sqrt(10)