Answer:

Step-by-step explanation:
STEP 1: Subtract 11x from 7x.
STEP 2: Subtract 10 from 12.
Answer:
Step-by-step explanation:
Answer:
120 books
Step-by-step explanation:
57 + 3 = 60
60 x 2 = 120
Yes, I think the answer is y = 7. The line x = 4 runs vertical (because all of the points in that line have an x-value of 4) so any line that is perpendicular to it has to be horizontal. Any line that is horizontal is in the form y = (some number). In order for the new line to run through the point (5,7) it would have to have the same y-value as that point, which is 7. So the new line is y = 7. Hope this helps :) (P.S. try graphing them both if you need a visual.)