90/15=6x4=24 Riley would on average score 24 points.
Y X
80 32
100 x'
80x' = 100*32
80x' = 3200
x' = 3200/80
x' = 320/8
x' = 40
The answer is: y=-4x+29
To solve this, you need to know the y-intercept.
1. y=-4x+b
2. 9+-4(5)+b
3. 9=-20+b
4. b=9+20
5. b=29
6. Substitute into y=-4x+b
