9r+r^2+8=0

Simple and best practice solution for 9r+r^2+8=0 equation. Check how easy it is, and learn it for the future. Our solution is simple, and easy to understand, so don`t hesitate to use it as a solution of your homework.

If it's not what You are looking for type in the equation solver your own equation and let us solve it.

Solution for 9r+r^2+8=0 equation: 



9r+r^2+8=0

a = 1; b = 9; c = +8;
Δ = b2-4ac
Δ = 92-4·1·8
Δ = 49
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{49}=7$


$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(9)-7}{2*1}=\frac{-16}{2}
=-8
$


$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(9)+7}{2*1}=\frac{-2}{2}
=-1
$

See similar equations:

| x-x(0.10)=250 | | 14w+w^2+30=0 | | x-x(0.30)=250 | | C(2)=3m+2 | | x-x(0.20)=250 | | 11a+a^2+18=0 | | 25(x)=30(48) | | 25(x)=30*48 | | x-x(0.25)=250 | | k-3(k+5)-0.5=3(0.25k+4) | | x-x(0.25)=450 | | x-x(0.20)=450 | | 11m-2=5m+1 | | 3y+18=5y-6 | | x-x(0.15)=450 | | 3y+18=12y-6 | | 19.64=4p | | n+1=2.6 | | (7-x)^2=121 | | 7x-3=2x-4 | | (12-x)(4-x)(4+x)=120 | | 6z⁴-25z³+32z²-+10=0 | | 1(x+9)=2 | | (35)(96)=32x | | 3x+4+7x-8+5x+2=45 | | 2x+20=3x+10=40 | | 8(3x+2)=4(5x+11) | | -9q+9.86=-2(7q+9.65)-9.84 | | 10x-8x+2+10=2x+12 | | 2x=1/64x= | | 3x+17=6x-5 | | (z+5)(z-7)=0 |

Equations solver categories