CHAPTER 4 REVIEW
The table shows the cost to mow a lawn for a given number of hours The table shows the cost to mow a lawn for a given number of hours. Find the rate of change in cost with respect to time. Time (hours) 2 6 10 Cost ($) 25 75 125
HINT: Find the SLOPE!! Answer: $12.50 PER HOUR
Plot the point (5, -2) and describe its location.
Quadrant IV
What is the value of the function when x = -7? f(x) = –2x + 9
f(-7) = 23
Plot the point (0, -3) and describe its location.
y – axis
Graph (use any method). SHOW ALL WORK!! y = -3x
y = -3x + 0 Slope: - 3/1 Y-Intercept: (0,0)
A) Sketch the graphs of the lines x = -5 and y = -3. B) Then, state the point at which the two graphs intersect:
A) x = -5 and y = -3 B) Point of intersection: (-5, -3)
Find the slope of the line that passes through the points: (-3, 7) and (5, -9)
m = -2 The slope is negative!
Tell whether (4, 9) is a solution of the equation Tell whether (4, 9) is a solution of the equation. Verify your answer algebraically. y = -4x – 7
No, (4, 9) is NOT a solution!! Because -23 does not equal 9!!
Find the slope of the line that passes through the points: (-2, -4) and (-2, 8)
The slope is undefined because it is a vertical line! m = undefined slope! The slope is undefined because it is a vertical line!
Graph by finding the x- and y- intercept. 4x – 5y = 20
x-int: (5, 0) y-int: (0, -4)
Tell whether the graphs of the two equations are parallel Tell whether the graphs of the two equations are parallel. Explain your reasoning. y = 9x – 2 and 9x + y = 18
They are not parallel because when you solve each equation for y, you get: y = 9x – 2 y = -9x + 18 The two slopes: 9 and -9 are not the exact same, and therefore the two lines are not parallel!
Find the value of x such that f(x) = 0. f(x) = -6x - 12
x = -2
Graph by finding the x- and y- intercept. 2y – 4x = 12
x-int: (-3, 0) y-int: (0, 6)
Graph by writing in slope-intercept form Graph by writing in slope-intercept form. Then, identify the slope and y-intercept. 2y = -5x - 8
Solve for y first! Slope: y – intercept: (0, -4)
Graph by writing in slope-intercept form Graph by writing in slope-intercept form. Then, identify the slope and y-intercept. 2x – 4y = 12
Solve for y first! Slope: y – intercept: (0,– 3)
Graph by writing in slope-intercept form Graph by writing in slope-intercept form. Then, identify the slope and y-intercept. y = –4
y = –4 y = mx + b y = 0x – 4 Slope: 0/1 or 0 y – intercept: (0,– 4)
Graph the equation by making a table of values: y = -3x + 4
y = -3x + 4 x y = -3x + 4 (x, y) -2 -3(-2) + 4; 6 + 4; 10 (-2, 10) -1 -3(-1) + 4; 3 + 4; 7 (-1, 7) -3(0) + 4; 0 + 4; 4 (0, 4) 1 -3(1) + 4; -3 + 4; 1 (1, 1) 2 -3(2) + 4; -6 + 4; -2 (2, -2)