(4x+3y=-13) * 2
(-5x+2y=-24)*3
_____________
8x+6y=-26
-
-15x+6y=-72
___________
23x=46
X=2
Answer: x = -6
Step 1: 2x = 4x+8+4
Step 2: 2x-4x = 12
Step 3: -2x = 12
Step 3: x = -6
11 as many fiction books as non fiction.
Fiction books F, Non Fiction NF
F: NF = 11 : 1
Total ratio 11+ 1 = 12.
Fraction of Fiction books F, = 11/12
Total books = 312.
Fiction books = 11/12 * 312 = 286
Fiction books = 286
Yes........its an identity
Answer:
4851 ways
Step-by-step explanation:
The fish have 3 choices. They can make it above, below, or though the pipe. Keep in mind there are 100 fish total:
group 1 + group 2 + group 3 = 100
If we keep group 3 (the fish that swim below the pipe) constant, say 1, and increment the other two (group 2 starting off at 1) we find 98 possibilities.
98 + 1 + 1 = 100,
97 + 2 + 1 = 100,
96 + 3 + 1 = 100
. . . 98 possibilities
Now we take group 1 as one greater (1 + 1 = 2) and then start incrementing group 2 starting from 1 as done before. So 97 + 2 + 1 = 100. Followed by 96 + 3 + 1, 95 + 4 + 1...97 possibilities
If we continue this pattern, we have 98 + 97 + 96... + 1 total possibilities to partition this school of fish.
98 + 97 + 96... + 1,
Sum = n(n + 1)/2 = 98(98 + 1)/2 = 98(99)/2 = 4851
