Simplify (frac{20}{5sqrt{28} – 2 sqrt{63}})
-
A.
(frac{5sqrt{7}}{7}) -
B.
(frac{5sqrt{5}}{7}) -
C.
(frac{7sqrt{5}}{7}) -
D.
(frac{7sqrt{7}}{5})
Correct Answer: Option A
Explanation
(frac{20}{5 sqrt{4 times 7} – 2sqrt{9 times 7}})
(frac{20}{10 sqrt{7} – 6sqrt{7}})
= (frac{20 sqrt{7}}{4 sqrt{7}})
= (frac{5sqrt{7}}{7})