If it's not what You are looking for type in the equation solver your own equation and let us solve it.
(5x+13)(x+1)=21
We move all terms to the left:
(5x+13)(x+1)-(21)=0
We multiply parentheses ..
(+5x^2+5x+13x+13)-21=0
We get rid of parentheses
5x^2+5x+13x+13-21=0
We add all the numbers together, and all the variables
5x^2+18x-8=0
a = 5; b = 18; c = -8;
Δ = b2-4ac
Δ = 182-4·5·(-8)
Δ = 484
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}$$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$$\sqrt{\Delta}=\sqrt{484}=22$$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(18)-22}{2*5}=\frac{-40}{10} =-4 $$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(18)+22}{2*5}=\frac{4}{10} =2/5 $
| d/4=32;56 | | 55+3x=25+8x | | 3x-2+2x-1=12 | | x/7-2.1=-12.4 | | 16d-15d+4=1 | | (X-3)=3(2x+6) | | -9/8+1/4u=-9/2 | | 1.84x-11=0.96 | | 15b-9b+4=16 | | 49=c+3.7 | | 12(2w=3)=6w | | x/9=7/36 | | 5(x-4)-3(x+2)=9x-20+x-5 | | 7-5x+8+2x+4x-3=2+3x5 | | 5/3+2/3x=35/12+7/4x+3/4 | | 64x+3,336x-82=68(50x+65) | | g+114.77=152.98 | | m/3.14159=7.3 | | 64x+3,336x-82=68 | | 8r+12=4-52 | | 1/2(x+8)=21 | | 5-2(x+8)=6x-7 | | 1j-87=165 | | 4+10-x/x=-2 | | 1j-87=418 | | 72=4u+8 | | 4x-2(x-2)=-3+5x+5 | | 6.5g+3=3.5g+9 | | 7m+14=8(3m+6) | | 2x-4(x-3)=-5+3x-13 | | 1=3d-2 | | 107-11b=-1b=37 |