Math 025 Section 7.2 Graphing
Objectives: to graph an equation in the form y = mx + b to graph an equation in the form Ax + By = C to solve application problems
Graph y = -3x + 2 2 y = -3x + 2 2 x y -2 5 2 2 -1
Graph: y = 3x – 5 y = 3x – 5 x y -1 -8 -5 1 -2
Graph: 2x – 3y = 6 2x – 3y = 6 -3y = -2x + 6 y = 2x – 2 3 x y -3 -4 -2 -2 3
Graph: x + 4y = 8 x + 4y = 8 4y = -x + 8 y = -x + 2 4 x y -4 3 2 4 1 y 2 4 1
x = a is always a vertical graph Problem: Graph x = 5 Find any two points that have 5 as the x-coordinate. y Draw the line. x = 5 x = a is always a vertical graph Problem: Graph y = -2 x y = -2 Find any two points that have -2 as the y-coordinate. Draw the line. y = b is always a horizontal graph
A local car dealer is advertising a 2-year lease on a Honda Civic A local car dealer is advertising a 2-year lease on a Honda Civic. The upfront cost is $3000 and the monthly payment is $150. The total cost, C, after x months is given by C = 150x + 3000. Graph this equation for 0 £ x £ 24. x C C = 150x + 3000 C 3000 12 4800 (18, 5700) 24 6600 5000 Total Cost The point (18, 5700) is on the graph. Write a sentence that describes this point. x 12 24 The ordered pair (18, 5700) means that the total cost of the lease for 18 months is $5700 months