-2x² + 5x - 5
= -2{x² - (5/2)x} - 5
= -2{x² - (5/2)x + (5/4)²} - 5 - (25/8)
= -2(x + 5/4)² - 65/8
if you are still confused, i want you to follow the related link that explains the concept of completing the square clearly.
Chat with our AI personalities
2x2-12x-54 = 0 Solve by factoring or using the quadratic equation formula or by completing the square: (2x+6)(x-9) = 0 Therefore: x = -3 or x = 9
2x2-10+7 = 0 Solving the quadratic equation using the quadratic formula will give you two solutions and they are: x = (5 - the square root of 11)/2 or x = (5 + the square root of 11)/2
2x2 = x2 - 2 Subtract x2 from both sides: x2 = -2 Take square roots: x = + or - i*sqrt(2) where i is the imaginary sqrt of -1.
2x2 = 228 divide both sides by 2 x2 = 114 x = ±√114 by the square root property
By using the quadratic equation formula: x = -5 and x = 3