If a(a + 7) = 18 and b(b + 7) = 18, where a ≠ b, then a + b = Pick one.
A) −48  B) −2  C) 2  D) −7  E) 48
a(a + 7) = 18 and b(b + 7) = 18   =&gt; a, b must be integers and if a is -9 or 2, b will be 2 and -9 respectively   =&gt; a+b = -7   Ans: −7
<result>D</result>
If a(a + 7) = 18 and b(b + 7) = 18, where a ≠ b, then a + b =