.9x(x-20)=830

Simple and best practice solution for .9x(x-20)=830 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 .9x(x-20)=830 equation:



.9x(x-20)=830
We move all terms to the left:
.9x(x-20)-(830)=0
We multiply parentheses
x^2-20x-830=0
a = 1; b = -20; c = -830;
Δ = b2-4ac
Δ = -202-4·1·(-830)
Δ = 3720
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:
$\sqrt{\Delta}=\sqrt{3720}=\sqrt{4*930}=\sqrt{4}*\sqrt{930}=2\sqrt{930}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-20)-2\sqrt{930}}{2*1}=\frac{20-2\sqrt{930}}{2} $
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-20)+2\sqrt{930}}{2*1}=\frac{20+2\sqrt{930}}{2} $

See similar equations:

| w=7w-841 | | 2-n+19=-7 | | 4-2(2x+1)=5x-14 | | 6m-2.1/2=m+12.1/2 | | 6(x-2=3x-2 | | 5x+3=13x+5 | | -4/5y-2/3(y-9)=3/5(y+15) | | 2x+x=315 | | 12x+8=15x+12 | | 3n=30+(n+2) | | d+-4d+2d+-2=0 | | n+23=11-n | | 5(10-2a)=a-5 | | 6t-8t+8=20 | | 4=0,5x | | x*0.02=366 | | 7x-39=2x+13 | | 10x+3=15x+5 | | 2q+16=5(q-7) | | 12m+-15m=12 | | 9x+3=11x+5 | | 9x+-3=11x+-5 | | 3t+16t+-8t-1=-12 | | 3t+16t+-8t-1=12 | | 3(4+v)=5(v-4 | | -7x+3=x+13 | | -7x-3=x+3 | | (3.6-2)+b=3.3 | | 6z-45=45 | | 15d+5=7d+37 | | 13z+-7z+-z=20 | | 11=z+194/28 |

Equations solver categories