Question 15
If $a \bullet b$ means the value of $ab + a + b$, and $5 \bullet x = 35$, the value of $x$ must be
(A) 5
(B) 7
(C) 9
(D) 12
(E) 15
(A) 5
(B) 7
(C) 9
(D) 12
(E) 15
MathNet 2015-part-06 — 191 problems (EN–VI) Question 15
Math Olympiad Vault · MathNet 2015-part-06 — 191 problems (EN–VI)