# Thread: Finding Solutions?

1. ## Finding Solutions?

5x^2+28x-49

What are the solutions? and how do I find them

2. Originally Posted by greenpumpkins
5x^2+28x-49

What are the solutions? and how do I find them
There is no equation => no solution

If the equation is $5x^2+28x-49=0$ then you can use the formula

$x = \frac{-14 \pm 21}{5}$

$x_1 = -7$ and $x_2 = \frac{7}{5}$

3. Originally Posted by running-gag
There is no equation => no solution

If the equation is $5x^2+28x-49=0$ then you can use the formula

$x = \frac{-14 \pm 21}{5}$

$x_1 = -7$ and $x_2 = \frac{7}{5}$
Uhh, running-gag, 5(49)+ 28(7)- 49= 245+ 196- 49 is certainly NOT 0!
Where did you get that formula?

4. Originally Posted by hallsofivy
uhh, running-gag, 5(49)+ 28(7)- 49= 245+ 196- 49 is certainly not 0!
Where did you get that formula?
$5(49)+28(-7)-49= 245-196-49=0$

5. Originally Posted by greenpumpkins
5x^2+28x-49

What are the solutions? and how do I find them
$
5x^2 + 28x - 49 = 0
$

$
a = 5
$

$
b = 28
$

$
c = 49
$

$x_{1,2} = \frac {-b \pm \sqrt {b^2 - 4ac}}{2a}
$