.The quadratic equation 2x^2 + bx + 18 = x^2 + 14 has a double root. Find all possible values of b.
+2281
The quadratic equation 2x^2 + bx + 18 = x^2 + 14 has a double root. Find all possible values of b.
2x2 + bx + 18 = x2 + 14
x2 + bx + 4 = 0
A double root of a quadratic equation means that both roots are the same.
The alternative is that the two roots of the quadratic equation are different.
For the equation to have a double root, b has to be twice the square root of 4.
b = 2 • sqrt(4)
b = 2 • + 2
so, b could be + 4
or, b could be – 4
