Answer:

Step-by-step explanation:
We have the following variables:
y: hours of sleep
x: age
Each day, a young person should sleep 9 hours
This means that y is 9 added to something
plus 1 4 hour for each year that the person is under 18 years of age.
For each year the person is under 18 years of age, she should sleep 1/4 = 0.25h on top of the 9 hours.
So the equation relating hours of sleep y and age x is:

Step-by-step explanation:
The coefficients of the y terms are -3 and 2. The least common multiple of 3 and 2 is 6. So multiply the first equation by 2 and the second equation by 3, so that the y terms have a coefficient of 6.
4x − 6y = 42
-18x + 6y = 21
The signs are opposite, so add the equations together.
-14x = 63
x = -9/2
The answer is: -3r+15r
you will multiply -3*5 first then -3*-r
I think the answer is: she got 36 right and you would have 2 rectangles for the wrong answers in the tape diagram and 9 for the right.
hope I helped...
this is answer for your problem