Answer:
12y + 5x - 15
Step-by-step explanation:
[tex]7y + 4x - 10 + 5y - 5 + x[/tex]
[tex]7y + 5y = (7 + 5)y = 12y[/tex]
[tex]12y + 4x - 10 - 5 + x[/tex]
[tex]4x + x = 4x + 1x = (4 + 1)x = 5x[/tex]
[tex]12y + 5x - 10 - 5[/tex]
[tex] - 10 - 5 = - (10 - 5) = - 15[/tex]
[tex] = 12y + 5x - 15[/tex]
