x2+15=20

Simple and best practice solution for x2+15=20 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 x2+15=20 equation:



x2+15=20
We move all terms to the left:
x2+15-(20)=0
We add all the numbers together, and all the variables
x^2-5=0
a = 1; b = 0; c = -5;
Δ = b2-4ac
Δ = 02-4·1·(-5)
Δ = 20
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:
$\sqrt{\Delta}=\sqrt{20}=\sqrt{4*5}=\sqrt{4}*\sqrt{5}=2\sqrt{5}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-2\sqrt{5}}{2*1}=\frac{0-2\sqrt{5}}{2} =-\frac{2\sqrt{5}}{2} =-\sqrt{5} $
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+2\sqrt{5}}{2*1}=\frac{0+2\sqrt{5}}{2} =\frac{2\sqrt{5}}{2} =\sqrt{5} $

See similar equations:

| 9=1.5x+6 | | 0.09−0.01(x+2)=−0.02(4−x) | | C=a/a+12.A | | 8y-15=14y-9 | | 5x-16=5x+8 | | 8(1.04^x)=16(1.06^x) | | 2^x-5=59 | | 4-6(x-1)=-14 | | 4(x+2)=2(x+9)-10 | | -5(3m-7)+16(m-3)=11-7 | | -7(p-1)-8=p+23 | | -2(x+2)+5=8(x+3)+6 | | 2(3a-1)-5a=10-6 | | C^2+15c+5c=0 | | 8-4(-x+5)=0 | | 0=-5x-20 | | 2(x+8)^2+80=48 | | -3(2c-9)=-3c-4(5c+6) | | 345=562.5-(7.5)x | | 6.4=9.1-0.3x | | 3q+8+10q=q+32 | | 3(-3x+1)-6=5(x-2)+15 | | 4/x+3=16/5x+11 | | x=1+26/35 | | 6y-5(y-3)+4=19 | | |-3-2u|=|4u-1| | | -3x^2-8=0 | | 4p−3=2p+8 | | 27=-b-30 | | 32.97=7g+3.92 | | -k-(-8k+7)=0 | | 3/4*x=5/8 |

Equations solver categories