Question

What is the exact value for the expression the square root of 56. − the square root of 14. + the square root of 126.? Simplify if possible.
the square root of 14.
4 the square root of 14.
2 the square root of 42.
8 the square root of 42.

Answer 1

Factor a square root of 14 out of every expression to get:

$\sqrt{14}*(\sqrt{4}-1+\sqrt{9)$

$\sqrt{14}*(2-1+3)$

$4*\sqrt{14}$

Thus, the expression is equal to four times the square-root of 14.  The second answer is correct.