first, you have to combine the 6x and the 10x you do this by subtracting 6x from each side. doing that you get....
-11=4x-51
then, you have to combine the -11 and the -51 you do this by adding 51 to each side. doing that you get....
40=4x
lastly, you need to divide each side by 4 to isolate the variable x. you get...
x=10
