Can someone explain the formula for this question?
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Answer:
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