Question

X^2-6x=b, make x the subject

Answer 1

x = 3 ±√(b + 9).

Explanation:

We use Completing the Square:

x^2 - 6x = b

(x - 3)^2 - 9 = b

(x - 3)^2 = b + 9 Taking square roots of both sides:

x - 3 = ±√(b + 9)

x = 3 ±√(b + 9).