Y-x =17
y = -x + 17
substitute this into the second equation
y = 4x + 2
-x + 17 = 4x + 2
0= 5x -15
15/5 = 5x/5
3 = x
20 total
6 have average of 5 years
6 x 5 = 30
20-6 = 14
14 have average of 8 years
14 x 8 = 112
112 + 30 = 142
142 / 20 = 7.1 years
Answer:
$8.10
Step-by-step explanation:
2.70+2.70+2.70=$8.10
1. 2. 3. total