Answer:
y = 40x + 150
Step-by-step explanation:
He starts with 150.
150
He adds 40 per month. Let x represent months: so every x, he gets 40. With 2 x, he gets 80: so we multiply 40 and x and add that to his starting number.
150 + 40x
And let's represent his end amount of money with y, and set it equal.
150 + 40x = y
For the other question:
x = number of months
Bob = 150 + 40x
Andrea = 100 + 50x
100 + 50x > 150 + 40x
50x > 50 + 40x
10x > 50
x > 5
So starting month 6, Andrea will have saved more than Bob.
