Solve 2x2 - 8x = -7
I need help, this is too confusing, please help

Question

Solve 2x2 - 8x = -7
I need help, this is too confusing, please help

anonymous · Answer

Is your problem: $$2 * 2 - 8x = -7$$ ?

anonymous · Answer

No, it's 2x^2 - 8x = -7

anonymous · Answer

Ok, so what you have is a quadratic. You can solve quadratics by making them equal to zero. To do this you will want to move the -7 to the other side to make it equal to zero. So you should have $$2x^2 - 8x + 7 = 0$$

anonymous · Answer

Alright, this is where I'm confused, I don't know what to do next

anonymous · Answer

Use the quadratic formula to solve for x http://www.purplemath.com/modules/quads/qform01.gif

campbell_st · Answer

use the general quadratic formula...

anonymous · Answer

Where our coefficients (a,b,c) come from $$ax^2+bx+c=0$$

campbell_st · Answer

or complete the square... its the same process

anonymous · Answer

Is it $$2\pm \sqrt{2}/2$$

jdoe0001 · Answer

is it?   what did you get anyway?

anonymous · Answer

What do you mean?

jdoe0001 · Answer

well... did you use the quadratic formula as recommended?
or did you complete the square?

anonymous · Answer

completing the square

anonymous · Answer

@mahone331 Yes, I got the same answer from using the quadratic formula.

anonymous · Answer

The answer is -60

anonymous · Answer

While completing the square and solving by factoring are two possible methods, they don't work every time. The quadratic formula will work for imaginary numbers and much larger integers. You should try using the quadratic a lot because you should have it memorized in college algebra.

anonymous · Answer

Thank you