How do you solve the quadratic using the quadratic formula given b^2-4b-14=-2b24b14=2?

1 Answer
Aug 12, 2016

Let the equation be x^2 - 4x - 14 = -2x24x14=2 so that the variables in our equation don't conflict with the parameters in the quadratic formula.

The quadratic formula is x = (-b +- sqrt(b^2 - 4ac))/(2a)x=b±b24ac2a, for equations of the form ax^2 + bx + c = 0ax2+bx+c=0.

Sending all our terms to one side:

x^2 - 4x - 14 = -2x24x14=2

x^2 - 4x - 14 + 2 = 0x24x14+2=0

x^2 - 4x - 12 = 0x24x12=0

Applying the formula:

x = (-(-4) +- sqrt((-4)^2 - (4 xx 1 xx -12)))/(2 xx 1)x=(4)±(4)2(4×1×12)2×1

x = (4 +- sqrt(16+ 48))/2x=4±16+482

x = (4 +- sqrt(64))/2x=4±642

x = (4 +- 8) /2x=4±82

x = (4 + 8)/2 and (4 - 8)/2x=4+82and482

x = 12/2 and -4/2x=122and42

x = 6 and -2x=6and2

Checking in the original equation , we have that both solutions work!

Therefore, the solution set is {x = 6" & "-2}{x=6 & 2}.

Hopefully this helps!