1400, as 1200 + 200 = 1,400 and 1600 - 200 = 1400.
First since the perimeter of this problem is P=2b x 2h I first multiplied 26 by 2 and got 52 inches. then I subtracted 52 from 180 and got 128. From there I divide 128 by 2 and I got 64 for the length
If 6 of the 13 books are new, then 7 of them are used. The ratio of new (6) to used (7) is
6:7 or 6/7
Ratio of all books (13) to used books (7) is
13:7 or 13/7
Okay well, if you make a graph, Point A (7,0) and Point B (4,6) are in the top right quadrant. and Point C (1,1) and Point D (5,3) are in the top left, top right, and bottom left quadrant (I'll link a photo of the graph.)
so the lines intersect and make it perpendicular
2x + 6 < x + 20
- x - x
x + 6 < 20
- 6 - 6
x < 14
Solution Set: (-∞, 14)