Heather works part time at a movie theater where she earns $7.00
per hour. The table shows how much money she makes for working
different numbers of hours. Heather wants to plot these data on a graph
with the number of hours on the horizontal axis and her income on the
vertical axis.
Hours 1 2 3 4 5 6 7 8 9 10
Earnings $7 $14 $21 $28 $35 $42 $49 $56 $63 $70

Suppose Heather decides to include data for up to 20 hours of work. She still wants to plot the data points on a 10-by-10 grid. Which of the following scales would be most reasonable to use for the horizontal axis?
a. 1 grid equals 20 dollars
b. 1 grid equals 5 hours
c. 1 grid equals 2 hours
d. 1 grid equals 1 hour

d. 1 grid equals 1 hour

Step-by-step explanation:

When plotting research data,  X-axis(or horizontal axis) usually used for independent variable and Y-axis is used for the dependent variable. In this case, Heather wants to know how much earning on different numbers of hours. The dependent variable is the earning and the independent variable is the hours, so you put hours on the horizontal axis.

You want to make a 10x10 grid of data and the hours ranged between 1-10. If you plot them equally, approximate scale will be: (10h-1h)/(10)= 0.9h/grid

The closest option is 1 hour per grid. It will provide the best visualization since it won't stretch or minimize the data too much.

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.