I figured out A. But can't get A. B. or D.?

a. Let x be the cost per square foot and y be the cost of the lot.

3000x + y = 373,000

-(4000x + y = 483,000)

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-1000x = -110,000

x = $110/ft²

y = $43,000

b. The cost of the lot and the price per square foot are constant, no matter what size the house is, so letting P be price and s be size,

P = 110s + 43,000

c. Use the equation from b.

1,000,000 = 110s + 43,000

s = 8,700 ft²

d. The domain is the size. [2,000, 8,700), or 2,000 ≤ s < 8700.

The range is the price. Find the price associated with 2,000 ft².

P = 110(2,000) + 43,000 = $263,000

The range is [263,000, 1,000,000), or 263,000 ≤ P < 1,000,000.

e. For the graph, plot an open circle at (8700, 1,000,000) and a closed circle at (2,000, 263,000). Draw a straight line between those two points.

a.(483000-373000)/(4000-3000)

=110$per square feet

b. y=110x+b

=373000=110(3000)+b

=373000=330000+b

=b=373000-330000

=b=43000

y=110x+43000

c. 1,000,000=110x+43000

110x= 1000000-43000

110x=957000

x=8700 feet square

d. domains 2000>x>0 range 263000>y>43000