ABC26GN1383 · Square Roots and Cube Roots

Subject: General Aptitude · Chapter: Square Roots and Cube Roots · Exam: · Marks: · Difficulty:

If $\sqrt{(x-1)(y+2)}=7, x$ and $y$ being positive whole numbers, then the values of $x$ and $y$ respectively are

(a)8, 5

(b)15, 12

(c)22, 19

(d)None of these

Answer

Answer (as printed): A

Explanation

$$\sqrt{(x-1)(y+2)}=7 \Rightarrow(x-1)(y+2)=(7)^{2} \Rightarrow(x-1)=7$$ and $(y+2)=7 \Rightarrow x=8$ and $y=5$.

Explanation as extracted from the printed page; notation may be imperfect.