3b - a = 45
a = 2b + 40
Solve simultaneously.
3b - (2b + 40) = 45
3b - 2b - 40 = 45
b = 45 + 40
b = 95min (1 hour 35 min)
a = 2 (95) + 40
a = 230min ( 3 hour 50 min)
Answer:

Step-by-step explanation:
4/5*3/3-1/3
4/5*3/3-1/3*5/5
4*3/15-5/15
4*3-5/15
12-5/15
7/15
You can prove it by the SAS postulate which should be the first option
1cm : 3m
to get from 12m to 3m you have to divide by 4, so if:
3 x 4 = 12
then you do the same to the 1cm and you get:
1 x 4 = 4
Therefore:
1cm : 3m
4cm : 12cm
the model is 4cm
the answer is the above in bold
hope it helped :)
and sry if my explanation wasn't detailed enough or if i misunderstood the question