CAT 2019 Slot 1 — QA Question 15
Solving Quadratic EquationsEasy
The number of solutions to the equation |x|(6 + 1) = 5 is
Answer & solution
Answer: 5
Solution
Since we have |x|, we will have to consider cases where, x < 0 or x = 0 or x > 0.
For x > 0: 6 + 1 = 5x ⇒ 6 − 5x + 1 = 0. The two roots of this equation are 1/2 and 1/3.
For x = 0, LHS = RHS, ∴ x = 0 is a root of the equation.
For x < 0: 6 + 1 = −5x ⇒ 6 + 5x + 1 = 0. The two roots of this equation are −1/2 and −1/3.
∴ Number of roots = 2 + 1 + 2 = 5.
Answer: 5.