Question

I. After how many weeks will Jennifer and William have the same amount of money in their bank accounts?

ii. How much will be in their accounts?

Answer 1

5 weeks

Explanation:

Find the equation of willam's account:

1. find rate x1-x2

44-30 plug in

14 =rate 30=y-intercept starting valuse is always intercept

44+14=58 check

f(x)= 10x+50

f(x)= 14x+30 solve

10x+50=14x+30 set values together

20=4x subtract 10x and 30 from both sides

x=5

Answer 2

• 5 weeks
• $100

Explanation:

Part i

Jennifer's account:

• f(x) = 10x + 50

William's account can be expressed as:

• g(x) = 14x + 30

Because the rate of change is 14 and y-intercept is 30

They will be same after x years, f(x) = g(x)

• 10x + 50 = 14x + 30
• 14x - 10x = 50 - 30
• 4x = 20
• x = 5

The accounts will be same after 5 weeks

Part ii

The amount in the accounts after 5 weeks:

• f(5) = g(5) = 10*5 + 50 = $100