Definitions
m = slope
b = y-intercept
X: 1 | 2 | 3 | 4 | 5
Y: -17 | -13 | -9 | -5 | -1
1) Find the slope
2) Describe the direction of the slope (positive, negative, zero, undefined)
Slope: 4
Direction: Positive
See white board for drawing.
Write the equation of the line "d" using (12,-3) as the ordered pair.
y = x +15
The cost of a school banquet is $95 plus $15 for each person attending.
Write an equation that gives
total cost as a function of the number of people attending.
What is the cost for 77 people?
y = 15x + 95
$1250
What does rate-of-change refer to
slope
Formula for Slope
Rise / Run
or
y2 - y1 / x2 - x1
X: -3 | -2 | -1 | 0 | 1
Y: 5 | 2 | -1 | -4 | -7
1) Find the slope
2) Describe the direction of the slope (positive, negative, zero, undefined)
Slope: -3
Direction: Negative
See white board for drawing.
Write the equation of the line "c" using (26, -3) as the ordered pair.
y = -2x + 49
Roman paid $150 to join a handball club. He pays an additional $15 every time he uses one of the club's handball courts. Write an equation that describes Roman's total cost for playing handball as a function of the number of times he plays.
Let C = the total cost and n = the number of times he plays.
C = 15n + 150
What is the equation for the line that passes through the coordinates (1,2) and (5, 10 )?
y = 2x
What does a horizontal line slope represent
zero slope
X: -4 | -2 | 0 | 2 | 4
Y: 6 | 6 | 6 | 6 | 6
1) Find the slope
2) Describe the direction of the slope (positive, negative, zero, undefined)
Slope: 0
Direction: Zero
See white board for drawing.
Write the equation of the line "b" using (20, 9) as the ordered pair.
y = 2x - 31
Billy plans to paint baskets. The paint costs $14.50. The baskets cost $7.25 each. Write an equation
that gives the total cost as a function of the number of baskets made. Determine the cost of four baskets.
C (x) = 7.25x + 14.50
$43.50
What is the equation for the line that passes through the coordinates (-4, 2) and (0, -5)?
y = (-7/4)x - 5
What does a vertical line slope represent
undefined slope
X: -5 | -2 | 1 | 4 | 7
Y: 10 | 5 | 0 | 5 | 10
1) Find the slope
2) Describe the direction of the slope (positive, negative, zero, undefined)
Slope = -5/3
Direction: Negative
See white board for drawing.
Write the equation of the line "a" using (-4, 11) as the ordered pair.
y = (-1/2)x + 9
Felicia Johnson paid $125 to join a tennis club. She pays an additional $5 every time she uses one of the club's tennis courts. Felicia does not want to spend more than $275 to play tennis during the summer. What is the
maximum number of times that she can play tennis on the club's courts for this amount?
30 times
What is the equation for the line that passes through the coordinates (5, -2) and (-4,-3)?
y = (1/9)x - (23/9)
What is the equation for slope-intercept form?
y = mx + b
X: 5 | 5 | 5 | 5 | 5
Y: 2 | 4 | 6 | 8 | 10
1) Find the slope
2) Describe the direction of the slope (positive, negative, zero, undefined)
Slope: Undefined
Direction: Undefined
See white board for drawing.
Write the equation of the line "e" using (12,-3) as the ordered pair.
y = -3
A real estate sales agent receives a salary of $250 per week plus a commission of 2% of sales. Write an equation that gives the weekly income y in terms of sales x.
y = 250 + 0.02x
What is the equation for the line that passes through the coordinates (1,5) and (4,1)?
y = (-4/3)x + (19/3)