Irene R. answered 04/06/20
BS in Mechanical Engineering and Certified math teacher for 13 years
The product of a number N and 9 can be written as 9N.
Next we would represent " that product added to 3 " as 3 + 9N
Then we could write the following equation using that fact the sum is "equal to the product of 3 and 13" :
3 + 9M = 3 • 13
To solve for N, use inverse operations:
3 + 9M = 3 • 13
3 + 9N = 39
3 + 9N - 3 = 39 - 3
9N = 36
9N/9 = 36/9
N = 4
Trenton F.
I found my notes and solved for 4 as well.04/06/20