Answer:
1.3 * c + 1.5
Explanation:
(5.2c-7) + (-3.9c + 8.5)
5.2 * c - 7 - 3.9 * c + 8.5
1. add constants ( - 7 and 8.5)
5.2 * c - 3.9 * c + 1.5
2. add both of the coefficients of c
when a variable is multiplied by a coefficient, we can add another coefficient * variable combination if the variable is the same. for example, 1 * x + 2 * x = 3 * x by adding the 1 and 2 together
similarly, 5.2 * c - 3.9 * c = (5.2 - 3.9) * c = 1.3 * c
1.3 * c + 1.5