Can someone explain the formula for this question?

Step-by-step explanation:

a) if the number of drill sold is plotted on the horizontal or x axis and the price of each drill sold is plotted on the vertical or y axis, the slope would be

m = (y2 - y1)/(x2 - x1)

= (40 - 50)/(3000 - 2000)

Slope, m = - 0.01

b)For every additional drill sold, the price per drill decreases by 0.01 cent

c) The equation of a straight line modelled in the slope intercept form is expressed as

y = mx + c

Where

m represents slope

c represents the y intercept

To determine the y intercept, we would substitute m = - 0.01, x = 2000, y = 50 into y = mx + c. It becomes

50 = - 0.01 × 2000 + c

50 = - 20 + c

c = 50 + 20 = 70

The equation modelling the situation is

y = - 0.01x + 70

Therefore, if the trend continues, the number of drills that would be sold for $43 is

43 = - 0.01x + 70

0.01x = 70 - 43 = 27

x = 27/0.01

x = 2700

2700 drills would be sold

$5.41

step-by-step explanation:

$20 - $14.51 = $5.49.