Answer:
Step-by-step explanation:
4
unit digit=4
cube=64
How many four element subsets of \{1, 2, 3, 4, 5, 6, 7\}{1,2,3,4,5,6,7} have 11 as an element but do not have 77 as an element
levacccp [35]
If we fix 1 to be an element of a subset of size 4, then we can choose from 5 other elements (2, 3, 4, 5, and 6) to fill the other 3 spots in the subset. So there are
such subsets.
They are simple linear equations with one unknown, lets tackle them, one step at the time solving for the unknown:
4x - 2(x - 5) = x + 13
4x - 2x + 10 = x + 13
2x + 10 = x + 13
2x - x = 13 - 10
x = 3
that is the solution.
3(6 - x) - 4 = 5x + 2(7x + 3)
18 - 3x - 4 = 5x + 14x + 6
14 - 3x = 19x + 6
14 - 6 = 19x + 3x
8 = 22x
x = 8/22 = 4/11
Answer: Subtract 9 to equal to negative four
Step-by-step explanation:
