Answer: x=1.5
Step-by-step explanation:
For this case we have the following functions:

By definition of composition of functions we have to:
So:

By definition of division of powers of the same base we have to place the same base and subtract the exponents:

ANswer:

Line D and C because they are not parallel but distorted or unsymmetrical
Its a simultaneous equation:
lets make "x" the used games and "y" the new ones
4x + 2y = 84
6x + y = 78. (multiply this by 2 to cancel out y)
12x + 2y = 156
so now we subtract them:
12x - 4x = 156 - 84
x = 9
used games cost $9
new games cost 78 - 6(9) = $24
Janet has $120 but she already bought 3 NEW games so:
120 - 3(24) = $48 left
48/9 = how many used ones she can buy = 5. something
she can buy 5 used
12a)
5x + 45 + 3x - 25 = 180
8x + 20 = 180
8x = 160
x = 20
12b)
2x - 5 = 2(20) - 5 = 40 - 5 = 35
3x - 25 = 3(20) - 25 = 60 - 25 = 35
y = 180 - (35+35)
y = 180 - 70
y = 110