Use the quadratic formula to solve the equation. Help Please!

2x^2-3x=-7

Question

Use the quadratic formula to solve the equation. Help Please!

2x^2-3x=-7

jamesj · Answer

First of all, what is the quadratic formula?  If you had a quadratic of this form:
$$ ax^2 + bx + c = 0 $$
what is the formula for the solutions?

anonymous · Answer

a = 2  b = -3 and c = 7

plug these into the formula

[-b +- sqrt(b^2-4ac)] /2a

jamesj · Answer

Right,
$$ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} $$

Now, write your equation in the standard form I did above.  Then find the values of a, b, and c.  Then put them into the equation.

anonymous · Answer

Ok this is my answer $$x= 3\pm \sqrt{47}/4$$
is that the answer?

anonymous · Answer

= --3 +-   sqrt (9 - 4*2*7)
  ----------------------
                  4

= (-3/4) +- sqrt(-47) / 4

anonymous · Answer

so, is two solutions?

anonymous · Answer

the roots are complex numbers 
 -(3/4) +-  (sqrt47 * i )/ 4

anonymous · Answer

yes 2 solutions

anonymous · Answer

is there any other way to express that solution. When I try to plug my answer it doesn't give you the choice for i.

anonymous · Answer

sorry - i made one error  its (3/4) not -(3/4)

anonymous · Answer

can you use the equation bottom so I can understand the answer. Is hard to look at it like that.

anonymous · Answer

ill try - i'm not very good at it - i'll draw it instead

anonymous · Answer

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