Question

x(x-2)-6=74

Answer 1

X(X - 2) - 6 = 74

First multiply out the brackets:

So, X(X - 2) -6 = 74 = XxX - 2xX - 6 = 74

(where X = the letter 'x' and x = multiplication)

So, X(X - 2) - 6 = 74 = X^2 - 2X - 6 = 74

Then subtract 74 from both sides of the equation:

X^2 - 2X - 6 - 74 = 74 - 74

X^2 - 2X - 80 = 0

Then factorise the equation:

X^2 - 2X - 80 = 0 = (X - 10)(X + 8)

(this part is a little bit trial and error. If you can't see what numbers to use just try out different multiples of 80 to see what works)

Then when X = 10 or X = -8 this equation equals zero.

So the solution to the equation is X = 10 and X= -8