Question

The following graph shows the amount of money Emma has in her savings account. The equation represented by this graph is: y = -10x + 110

A: How much money will Emma have after 10 weeks?

B: At how many weeks will Emma have $50 dollars in her account?

Answer 1

Answers
A. She will have $10
B. At 6 weeks she will have $50

Step by step

A. We know the equation is y= -10x + 110

x = weeks, here it says 10 weeks so sub 10 for x

y= -10(10) + 110
y = -100 +110
y = 10
Emma will have $10 at 10 weeks

B. By looking at the graph you can see the line crosses the y value of $50 at the x value of 6 weeks

You can also solve this with the equation

y= -10x + 110

Y is the $ value of $50, sub into equation and solve for x

50 = -10x + 110
Subtract 110 from both sides to isolate variable

50 - 110 = -10x +110 -110
Simplify

-60 = -10x

Divide both sides by -10 to solve x

-60/-10 = -10/-10x

6 = x

So at 6 weeks Emma has $50