x + 77 = 3(x - 6)
x + 77 = 3x - 18
x + 77 + 18 = 3x - 18 + 18
x + 95 = 3x
x + 95 - x = 3x - x
95 = 2x
x = 95/2
x = 47.5
15 x 45 = 675
45 x 135 =6075
Answer:
no
Step-by-step explanation:
The set of perfect squares includes {0, 1, 4, 9, 16, 25, ...}.
Subtracting a couple of the elements, we get ...
4 - 1 = 3 . . . . not a member of the set
The set is NOT CLOSED under subtraction.