13. Solve –5√ x = –15. A. x = –9 B. x = –7 C. x = 9 D. x = 7

Mathematics

1 answer:

ddd [48]2 years ago

4 0

$Domain:x\geq0\\\\-5\sqrt{x}=-15\qquad\text{divide both sides by (-5)}\\\\\sqrt{x}=3\to \boxed{x=9}\to\boxed{C.}$

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