Three students that share a townhouse find that their electric bill for October is $4.85 less than the September bill. The total of both bills is $268.45, and each bill is split evenly among the roommates. How much did each owe in September?

$45.55

Step-by-step explanation:

268.45=x+x-4.85

2x= 273.30

x= 136.65

136.65÷3=45.55

September is x and October is x-4.85

When you add 4.85 to 268.45 you get 2x=273.30.

273.30 is the amount of money payed in September x2.

273.30/2 is the amount of money paid in September.

136.65÷3 is $45.55. This is how much they payed in September.

if the eqn of the parabola is f(x) = (x-4)(x+2), we need to mult. this out to find the coordinates of the vertex.

then f(x) = x^2 + 2x - 4x - 8, and f(x) = x^2 - 2x - 8.

one way in which you can find the vertex is to calculate x = -b / (2a).   here, that comes to

        )

x = = 1.   f(1) = 1^2 - 2(1) - 8 = - 9.   vertex is at (1, -9).

        2(1) 

find another point on the curve:   let x=0, for which y=-8.   then (0, -8) is on the curve.   plot the vertex and this point and draw a smooth parabola thru both.

hope this

do i do it on a graph?

step-by-step explanation: