Answer:
A+3B=4+5r
Step-by-step explanation:
Given that,
A = 1+r+7r
B = 1-r
We need to find an expression that is equal to A+3B.
Putting the values of A and B in A+3B, we get :
A+3B = 1+r+7r + 3(1-r)
=1+8r+3-3r
=(1+3) +(8r-3r)
=4+5r
Hence, the values of A+3B equals 4+5r.
