The given expression is
[tex]-c+5d+7c-11d+d-3c[/tex]To simplify this expression, we have to reduce like terms. -c, 7c, and -3c are like terms. 5d, -11d, and d are like terms.
Let's group them.
[tex]-c+7c-3c+5d-11d+d[/tex]Now, we have to follow the rules for sums and subtractions. Notice that -c, 7c, and -3c are equal to 3c because -1+7-3=3. Also, 5d, -11d, and d are equal to -5d because of 5-11+1=-5.
[tex]3c-5d[/tex]