Answer:
The cost is y = $185
Step-by-step explanation:
Let us have points spelt out here
(2500,125) and (3200,146)
The general form of a straight line equation is;
y = mx + b
where m is slope
So to calculate the slope in this case, we have
m = (146-125)/(3200-2500)
m = 21/700 = 0.03
So we have the equation as
y = 0.03x + b
To get b, we use any of the two points
Let us use (2500,125)
So we have
125 = 0.03(2500) + b
125 = 75 + b
b = 125-75
b = 50
So the complete equation of the line is;
y = 0.03x + 50
So here, we want to find the cost of a house with 4500 square feet
simply substitute 4,500 for x
y = 0.03(4500) + 50
y = 135 + 50
y = $185