To solve for x we must get it on one side by itself. Since x is being multiplied by 5.1, we must then divide both sides by 5.1 in order to essentially 'cancel out' the coefficient of x on the left side so that we then get x by itself:
[tex] 5.1x=1.02 [/tex]
[tex] \frac{5.1x}{5.1}=\frac{1.02}{5.1} [/tex]
[tex] x=0.2 [/tex]
So now we have solved for x and x = 0.2.