Answer:
No solution
Step-by-step explanation:
-x + y = 8..............(1)
1/2x - 1/2y = 3......(2)
Multiply (2) by 2
x - y = 6 ............(3)
Adding (1) and (3)
-x + x + y - y = 8 + 3
x and y are both eliminated so no solution
Food = 1/4
gasoline = 3/5
Total = 1/4 + 3/5 = 17/20
17/20 = 272
1/20 = 272 ÷ 17 = 16
20/20 = 16 x 20 = $320
This is a combination in which you choose 4 from 10.
The formula is
combinations = 10! / 4! * (10-4)!
combinations = 10! / 4! * 6!
combinations = 10 * 9 * 8 * 7 * 6! / 4! * 6!
combinations = 10 * 9 * 8 * 7 / 4 * 3 * 2
combinations = 10 * 3 * 7
combinations = 210
Source:
http://www.1728.org/combinat.htm
Her statement is possible, the first rectangle could be equal to the second because x is unknown so if x was 5in in the first rectangle and - 1 in the second rectangle both problems would look like this 2 in & 5 in and the second one 5in & (2 in = (-1 +3)).