Given:
There is a bicycle that is cost $175
There are two friends:
The first has $45 and save $5 each week
So, we have the following equation, let (x) is the number of weeks

Solve the equation to find (x):

So, the first can buy the bicycle after 26 weeks
The second friend has an amount (y) after (x) weeks according to the shown graph of the line:
As shown the line passes through the points (0, 15) and (3, 39)
The slope of the line represents the saving each week =

The y-intercept represents the initial saving = $15
So, after (x) week we have the following equation:

Now, solve to find (x)

So, the second can buy the bicycle after 20 weeks
So, the answer will be