How do you solve 2x^2 + 2x – 1 = 0?

1 Answer
Shantelle
Jul 18, 2018

x = (-1 +- sqrt3)/2

Explanation:

To solve this, we will use the quadratic formula. We know that this is in standard quadratic form, or ax^2 + bx + c, where a = 2, b = 2, and c = -1.

The quadratic formula is:
x = (-b +- sqrt(b^2 - 4ac))/(2a)

Now plug in the values of a, b, and c into the formula to find the value of x:
x = (-2 +- sqrt(2^2 - 4(2)(-1)))/(2(2))

x = (-2 +- sqrt(4 + 8))/4

x = (-2 +- sqrt12)/4

x = (-2 +- 2sqrt3)/4

x = (-1 +- sqrt3)/2

Hope this helps!

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