Kate: Please, for clarity, use " ^ " to denote exponentiation: 2x^2 + x − 4 = 0
And please include the instructions.
2x^2 + x − 4 = 0 can be re-written: 2(x^2 + (1/2)x - 2) = 0
Dividing both sides by 2 results in x^2 + (1/2)x - 2 = 0
Let's "complete the square:" x^2 + (1/2)x + (1/4)^2 - (1/4)^2 = 0
Then (x+(1/4))^2 = (1/4)^2
Taking the sqrt of both sides: x+1/4 = plus or minus 1/4
Solving for x: x = -1/4 plus or minus 1/4
Solving for x (continued): x = 0 and x = -1/2
