Complete the square for the equation x^2 - 12x + 8 = 0
To complete the square, we will need to put the equation into the form (x - a)2 - b + 8 = 0, where a is half of the coefficient of x (12 in this case) and b is the value we need to subtract in order for the new form of the equation to be equivalent to the original. To begin we initially get (x - 6)2 - b + 8 = 0 since 6 is half of 12. To find b we expand (x-6)2 to get x^2 - 12x + 36 so we realize we need to subtract 36. So our equation is (x - 6)2 - 36 + 8 = 0 which we can simplify to (x - 6)2 - 28 = 0.
MJ
Related Maths GCSE answers
All answers ▸Solve algebraically the simultaneous equations: x^2 + y^2 = 25 and y – 3x = 13
Minnie and Helen are playing in the same hockey match. The probability of Minnie scoring a goal is 0.3. The probability of Helen scoring a goal is 0.4. What is the probability of both Minnie and Helen scoring a goal.
f(x) = (x+1)^2 and g(x) = 2(x-1); Show that gf(x) =2x(x+2)
Find ∫(4x - 2/(x^3)) dx