Question

Simplify the expression 2√ 20 − 3√ 7 − 2√ 5 + 4√ 63 .

A. 2√ 20 − 3√ 7 + 4√ 63
B. 2√ 5 + 9√ 7
C. 2√ 20 − 3√ 7 − 2√ 5 + 4√ 63
D. 2√ 20 − 4√ 7 − 2√ 5

Answer 1

Simplify √20 to 2√5

2 * 2√5 - 3√7 - 2√5 + 4√63

Simplify √63 to 3√7

2 * 2√5 - 3√7 - 2√5 + 4 * 3√7

Simplify 2 * 2√5 to 4√5

4√5 - 3√7 - 2√5 + 4 * 3√7

Simplify 4 * 3 √7 to 12√7

Collect like terms

(4√5 - 2√5) + (-3√7 + 12√7)

Simplify

2√5 + 9√7

Answer: B