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
Answer:
n=14
Step-by-step explanation:
multiply both sides by two to get rid of 1/2 and you find n=14
You have to first make like terms
**you want the denominator to be 21
Answer:
c
Step-by-step explanation:
substitute (2,1) and (5,4) into each equation
2-1=1 and 5-4=1 so c is correct
