Find x in ecuation 4x+30=40

2.5

4x+30=40

-30 - 30

4x=10

/4 / 4

x=2.5

4x+30=40

What you would do is subtract 30 from 30 and 40 which would give you 10 and then what you would do is divide the 10 by 4 to get 2.5. Therefore X=2.5. And to check your work you would plug in 2.5 in place of X and the answer to that equation should be 10.