8.6x + 3 + 8.6+3 =. 17.2x + 6
5.2+5.2= 10.4
17.2x + 6 = 10.4
I will assume that the two equations are
1) y = -x^2 +2x + 4 and 2) x +y = 4
subtract 2 from 1 and you get
y -x - y = -x^2 + 2x + 4 - 4
-x = -x^2 +2x
x^2 -x -2x = 0
x^2 - 3x = 0
x(x-3)=0
x=0 and x - 3 =0
x=0 and x = 3
Then y = 4 - x
y = 4 - 0 and y = 4 -3
y = 4 and y =1
Solutions:
Points (0,4) and (3,1)
The average change per hour is B 40.7
to solve this we need to isolate the x variable.
subtract 1 from each side: [3x+4] = 6
now we can drop the parentheses and subtract 4 from each side: 3x = 2
divide each side by 3: x = 2/3
