4x(x-5)=80

Simple and best practice solution for 4x(x-5)=80 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 4x(x-5)=80 equation:



4x(x-5)=80
We move all terms to the left:
4x(x-5)-(80)=0
We multiply parentheses
4x^2-20x-80=0
a = 4; b = -20; c = -80;
Δ = b2-4ac
Δ = -202-4·4·(-80)
Δ = 1680
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:
$\sqrt{\Delta}=\sqrt{1680}=\sqrt{16*105}=\sqrt{16}*\sqrt{105}=4\sqrt{105}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-20)-4\sqrt{105}}{2*4}=\frac{20-4\sqrt{105}}{8} $
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-20)+4\sqrt{105}}{2*4}=\frac{20+4\sqrt{105}}{8} $

See similar equations:

| 5k-(6+k)=-(4K+6) | | 2^1-x^2=1/256 | | 300=25x+10x | | -7(x-3)=-5(x-3)-2 | | (5x-17)+(2x+50)=180 | | 73=y=9 | | -2(45-2x)x-2(24-2x)+(24-2x)(45-2x)=0 | | -3^2(m+2)=10(3-m) | | Y=250x4 | | 100=t/0.5 | | 2^2x-1=64 | | 4n-36=148 | | 0.06b=6 | | y+77=180 | | -11=m-4,m^2+m | | N/4=3,n^2-1 | | 9n-7=30 | | 75+x+15=180 | | x⁴+3x+20=0 | | 5+x+15=180 | | 9(4+v)+38v=10v | | 7(x-3)=-2x+42 | | -4(5-3b)=6b+4 | | 36-8x=x | | 0.36*2x=27 | | 3v+8=7v | | x-(2x-3)=90 | | a=8.1-2.8 | | 43=4v-9 | | (2x-3)-x=90 | | z=1-3 | | x/3-2=2x+8 |

Equations solver categories