8r2+9r+1=0

Simple and best practice solution for 8r2+9r+1=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 8r2+9r+1=0 equation: 



8r^2+9r+1=0

a = 8; b = 9; c = +1;
Δ = b2-4ac
Δ = 92-4·8·1
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*8}=\frac{-16}{16}
=-1
$


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

See similar equations:

| 2u2+8u+8=0 | | 34=y/5+14 | | 285m-60=45 | | 314^2=3.14r^2 | | 16^2=10x | | 31.75r-6.75=1.25 | | 123b-55=8.50 | | 10=40-2.5x | | (x+5)(7(x)-21)=0 | | 7x-24=4x+54 | | x^2-7x-23=0 | | 3j+12=69 | | 4x+6-9+(x+5)=10 | | x+1.4/3=9 | | 3+6(x+3)=42 | | 7/3-4m/5=2m/3-3/5 | | -(0.5-2x)=(3x-1)*(-0.9)+0.1 | | 90=1/2(x(10)) | | 152-n=8 | | 4x-+7=8x+33 | | 6*(11^((2x-7)))=78 | | 40+36-p=-25 | | (D+22)+(d)=90 | | 0.25x+115=180 | | 0.3x-45=45 | | 0.1x-31=45 | | 4^x+3=8^2x | | 5p+12=-18 | | 7x+7=+10x-38 | | f(2)=2(2)^3-3(2)^2+7 | | 7.5x=85.75 | | f(-1)=2(-1)-3(-1)^2+7 |

Equations solver categories