Posted by **-Untamed-** on Monday, December 5, 2011 at 7:42pm.

Solve the following quadratic equation(as exact values) using the quadratic formula.

x^2-10x-15=0

I got 5+-2sqrt10/2.

^ Sorry hard to write it out. But basically there is a 5 there, the negative sign is supposed to be under the positive sign, then there is a two outside of the radicand, and inside the radicand is 10, all under 2.

- Math -
**MathMate**, Monday, December 5, 2011 at 8:06pm
The answer is correct if it was meant to be, after cancelling the two's:

5±√(10)

- Math - correction -
**MathMate**, Monday, December 5, 2011 at 8:10pm
The answer is correct if it was meant to be (without the 2 in the denominator):

5±2√(10)

- Math -
**-Untamed-**, Monday, December 5, 2011 at 8:15pm
Where does that two in the denominator go? Since it has to cancel out with all terms.

- Math -
**MathMate**, Monday, December 5, 2011 at 8:52pm
x=(-b±sqrt(b²-4ac))/2a

a=1

b=-10

c=-15

so substituting,

x=(10±sqrt((-10)²-4(1)(-15)))/2

=(10±sqrt(160))/2

=(10±4sqrt(10))/2

=5±2sqrt(10)

You may have (like I did) subtracted 4ac (and got 40) instead of adding to get 160.

## Answer this Question

## Related Questions

Math - Use the quadratic formula to solve each of the following quadratic ...

math - (4.35E-2 - x)(7.56E-2 -x ) ============================ (0.324 + 2x)2 ...

quadratic equations - can you solve the equation using the quadratic formula x2...

Math - How do you graph the quadratic formula x^2-10x=11? Here's what I got so ...

Math - Solve the given quadratic equation exactly using the quadratic formula. ...

Math - Solve the given quadratic equation exactly using the quadratic formula. ...

math - 15t^2+7t=2 The quadratic formula tells you that the solutions are: t = [-...

algebra II - I'm quite clueless as to how to solve this. I know the quadratic ...

Math ,help - how can i simplify this more its for the following problem: Problem...

help with solving - x^2+(x-2)^2 = (2x-6)^2 solve for x. thanks so much. Please ...