SOLUTION
Step 1: Find the area of the wall.

Step 2: Find the cost of wallpaper per square foot


The correct answer is B: $0.72
Answer:
My answer is b
sorry if its wrong.
Step-by-step explanation:
Answer:
The run is -7.
Step-by-step explanation:
Since we know that slope = rise/run, we can calculate the run by inputting the given numbers.
So,
-3 = 21/x and we need to solve for x.
When we cross multiply we get -3x=21.
Then, divide -3 on both sides and x = -7