Solve: 2x^2 + x = x^2 - 4(x+1)

First we need to start by multiplying the brackets on the right, which will give us:2x^2 + x = x^2 - 4x - 4Then we need to move everything that is on the right to left:2x^2 + x - x^2 + 4x + 4 = 0Here a common mistake is that students to change the signs to " - x^2" and "+4x" and "+4"Our new equation will be:x^2 + 5x + 4 = 0Then we use The Quadratic Formula:x1 = (- b + sqrt(b^2 - 4ac)) / 2ax2 = (-b - sqrt(b^2 - 4ac)) / 2a4) In our case the results will be:x1 = ( -5 + sqrt(25 - 16)) / 2 || Note: sqrt(25-16) = sqrt(9) = 3 ||x2 = ( -5 - sqrt(25-16)) / 2This will give us the results of:x1 = -1x2= -4