If it's not what You are looking for type in the equation solver your own equation and let us solve it.
3d+d+2d=18
We move all terms to the left:
3d+d+2d-(18)=0
We add all the numbers together, and all the variables
6d-18=0
We move all terms containing d to the left, all other terms to the right
6d=18
d=18/6
d=3
| 4a/100-90=a/400+537 | | -2x+3=-23 | | 4x+9=6x–11 | | Y2/7=y | | 4x–19–6x=x+1 | | 8a–6=-14a+38 | | 4=r2 | | 10u-2u=24 | | -7+7p=0 | | j+4j-4j-j+3j=14 | | 9n+17= | | -7+x+11=14 | | x2−7=−10 | | 4x+14+8x-8+5x-6+6x+7x+120=720 | | a+3,178=6000 | | 2(a–18)=–8 | | -22-x=39 | | 2(z+5)=3(4z+2)-1 | | f(15)=50,900(1.03) | | -2x+25=25-2x | | x+1.25=x+10 | | 10z-10=-30 | | -8-x-1-2x=2x-10 | | F(x)=55+0.12x | | 80=x/15 | | –3h=–12 | | P(x)=-7x-5x2+2x3+8x4+10x5 | | 20d+5.75=43 | | 8=2r−10 | | 7(k-20)=7 | | (2.1x+4.3)-(-3x-7)=5.1x-2.7 | | 9b+21=417 |