Respuesta :
We are given the following data in tabulated form:
Call minutes, y Bill Amount ($), x
125 75
150 85
175 95
200 105
We can see that for every 25 increase in call minutes, there is a constant 10 increase in bill amount. Therefore the equation relating the two variables is linear. The call minutes is y while the bill amount is x, therefore:
y = m x + b
where m is the slope and b is the y-intercept
Calculating for the slope m:
m = (y2 – y1) / (x2 – x1)
m = (150 -125) / (85 – 75)
m = 2.5
So, y = 2.5 x + b
Calculating for b using the 1st pair:
125 = 2.5 (75) + b
b = - 62.5
So the final equation is:
y = 2.5 x – 62.5
To match, simply plug in the value of the bill amount ($) as x in the equation and the answer will be y which is the call minutes.
in case u didn’t wanna do the math:
128 = $76.20
132= $77.80
134= $78.60
144= $82.60