3x+8x+4x=6x+63
First, since almost everything is together, combine like terms
15x=6x+63
Now, subtract 6x from both sides
9x=63
Now divide both side by 9
x=7
Now that we have found what x equals, we need to plug in the variable into 5x+23
5(7)+23
Now just simplify
35+23= 58
Therefore, 5x+23 when x=7 is 58
