Answer: 82.40
Step-by-step explanation: I took the quiz
Plot the graph then you do the vertical line test. You draw a vertical line on the graph. If the line touches the graph at just one point,note just one point then it is a function
For this case, the first thing we must do is define a variable.
We have then:
x: unknown number
We now write the equation that models the problem:

From here, we clear the value of x.
We multiply both sides of the equation by 2:

We subtract 30 on both sides of the equation:

Answer:
The value of the unknown number is given by:

Answer:
The next mark should be at (3,-3)