Is the equation linear? If yes, write in standard form.
x = y - 5
yes; x - y = -5
100
Find the rate of change.
x y
3 -6
5 2
7 10
9 18
11 26
4
100
Name the constant of variation.
y = (-4/5)x
k = -4/5
100
Determine whether the following sequence is arithmetic.
18, 16, 15, 13, ...
no
100
Is the following relationship proportional? Explain.
x 1 2 3 4 5
y 75 150 225 300 375
Yes. Because the ratio between x and y is constant and the line with pass through the origin.
200
Graph the following equation by using the x- and y-intercepts:
x + 2y = 4
[see p.159 # 9]
200
Determine whether the function is linear.
x -7 -4 -1 2 5
y 5 4 3 2 1
Yes; the rate of change is constant
200
Suppose y varies directly with x. Write a direct variation equation, then solve.
If y = 15 when x = 12, find y when x is 32.
y = (5/4)x; 40
200
Determine whether the following sequence is arithmetic.
4, 9, 14, 19, ...
yes; d = 5
200
Write an equation in function notation for the following graph.
f(x) = 2x
300
Determine the x- and y-intercepts of the equation
6x + 2y = 8
x: 1.3
y: 4
300
Determine whether the function is linear.
x 8 12 16 20 24
y 7 5 3 0 -2
No, the rate of change is not constant
300
Graph the equation.
y = -7x
[see p. 186 #17]
300
Find the next 3 terms in the arithmetic sequence.
12, 9, 6, 3, ...
0, -3, -6
300
Write an equation in function notation for the following graph.
f(x) = 3x - 2
400
Solve the following equation by graphing (find the root).
12x + 132 = 12x - 100
no solution
400
Find the slope of the line passing through the points (8,-2) and (1,1)
m = -3/7
400
Write and graph a direct variation equation that relates the variables.
"Music downloads are $0.99 per song. The total cost of d songs is T."
T=0.99d
400
Write an equation for the nth term of the following arithmetic sequence. The graph the first 5 terms.
15, 13, 11, 9, ...
= 17 - 2n
400
For the arithmetic sequence, determine the related function. Then, determine whether or not the relation is proportional or non-proportional.
-4, 0, 4, ...
f(n) = 4n - 8; non-proportional because the graph will not pass through the origin.
500
Parts of New Orleans lie 0.5 meters below sea level. After d days of rain, the equation w = 0.3d - 0.5 represents the water level w in meters.
Find the zero and explain its meaning within the context of the presented problem.
about 1.67; would take approximate 1.67 days of rain to reach sea level
500
Find the slope of the line passing through the points (6,-10) and (6,14)
undefined
500
A map of North Carolina is scaled so that 3 inches represents 93 miles. How many miles apart are Raleigh and Charlotte if they are separated by 1.8 inches on the map? Round to the nearest tenth.
55.8 miles
500
Kaia has $525 in a savings account. After one month of saving she has $580 in the account. At the end of the next month the balance is $635. The balance at the end of the third month is $690. Write a function to represent the arithmetic sequence, the graph.
= 55n + 525
500
Write an equation to fit the data in the table.
Hour 1 2 3 4
Inches 1.65 3.30 4.95 6.60