-9 (c + 7) = -13c + 7​

c=17.5

Step-by-step explanation:

-9(C+7) = -13c + 7

-9c - 63 = -13c + 7

-9c + 13c = 7 + 63

4c = 70

c = 17.5

For this case we have the following functions:
 g (x) = 3 ^ x + 1
 f (x) = 3x + 1
 We observe that the graph of both functions are cut in the value of:
 x = 1
 Therefore, the value of the functions is the same for that value of x.
 Let's check it: g (1) = 3 ^ 1 + 1 = 3 + 1 = 4
 f (1) = 3 (1) + 1 = 3 + 1 = 4
 
 ƒ (x) = g (x) is a true statement for:
 x = 1