If (x+6) is a factor of x2+mx-48, then m=
A)16
B)12
C)2
D)6
E)14

Question

Quizplus · Accepted Answer

This is a quadratic equation. Use the formula if and b are solutions of a quadratic equation then it can be expressed as x2 + (a-b) x - ab = 0
or (x+a) (x-b) = 0
Given x+6 is a factor So a= 6
(a-b) = m and ab =-48
Hence b = 8 and m =2
Key takeaway: The general form of a quadratic equation is x2 + (a+b) x + ab = 0 and can be expressed as product of two terms (x+a)(x+b) = 0, a and b are called two roots or solutions of the equation The values x =a or b satisfy the equation.

If (X+6) Is a Factor of X2+mx-48, Then M=