If it's not what You are looking for type in the equation solver your own equation and let us solve it.
x2+9x+15=0
We add all the numbers together, and all the variables
x^2+9x+15=0
a = 1; b = 9; c = +15;
Δ = b2-4ac
Δ = 92-4·1·15
Δ = 21
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(9)-\sqrt{21}}{2*1}=\frac{-9-\sqrt{21}}{2} $$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(9)+\sqrt{21}}{2*1}=\frac{-9+\sqrt{21}}{2} $
| 3(3y+3)+4y=-23 | | 5(2)^x-1=80 | | 1/2r-12=-27 | | 15(2-k)=k+6(2k-3) | | -1/6r+1=3 | | 3x+9-5(2x-7+6=50 | | 4x-1=x=11 | | -9r−8=10−6r | | -10+7q=6q | | 5x-100x=50 | | 3a-a-1=23 | | n^2-n-720=0 | | h=7+2h | | 9c=10+10c | | 25x-15+16x-2x+x=180 | | −8x−33=5x−7 | | x+(x+20)+(2x+10)+(X+40)=360 | | 1,290=h/10+h/5 | | 25x-15=16x-2x | | 4x-38=3x+2/5 | | 3x-0,01x^2=0 | | 38=8n+6 | | A=1/2x25x30 | | x^=64 | | 84=11n+7 | | -19=6+5t | | 3x-32-16x=-2x | | X^2-3=10x | | 14=4n+2 | | 12=-2t+10 | | 4-c=5 | | 2a+2a-a-35=3a-4a-5 |