Find the constant of variation if y varies directly as x,
and y = 95 when x = 19.
5
100
(75, 30) (r, 18)
Find r.
r = 125
100
Four friends on a ski trip pay $210 each to share the rent of a cabin. The cost per person varies inversely as the number of persons. How many people sharing the rent would make the cost $120 per person?
7 people
100
Find the vertex and give the least value of
f(x) = x^2 + 8x + 3
vertex: (-4, -13)
least value: -13
200
f(x) = 3x - 2
Find f(x) = 0
x = 2/3
200
x1 = 72, y1 = 5
x2 = ??, y2 = 2
48
200
x1 = 20, y1 = 5
x2 = ??, y2 = 50
2
200
The number of units manufactured varies directly with the number of hours worked. If 10 units are manufactured in 4 h, how many units are manufactured in 14 h?
35 units
200
Find the vertex and give the greatest value of
f(x) = 2x - x^2.
vertex: (1, 1)
greatest value: 1
300
f(x) = x^2 + 2x and g(x) = 5x
Find f[g(x)].
120
300
x1 = ??, y1 = 70
x2 = 2, y2 = 25
5.6
300
x1 = 10, y1 = 75
x2 = 30, y2 = ??
25
300
The amount of interest earned on savings is directly proportional to the amount of money saved. If $104 interest is earned on $1300, how much interest will be earned on $1800 in the same period of time?
$144
300
Find the coordinates of the vertex and the equation of the axis of symmetry of the graph of the equation y = 2x - x^2. Use the vertex and at least four other points to graph the equation.
vertex: (1,1)
axis of symmetry: x = 1
400
f(x) = x^2 and g(x) = 2x
Find f[g(1)]
4
400
D = {1, 3, 5}
R = {2, 4, 5, 6}
Is this a function?? Why?
No. Because the domain is repeated.
400
D = {1, 2, 3}
R = {5, 10, 15}
State the inverse.
D = {5, 10, 15}
R = {1, 2, 3}
400
If a 24g mass is 30 cm from the fulcrum of a lever, how far from the fulcrum is a 45g mass that balances the 24g mass?
16 cm
500
f(x) = x^2 and g(x) = 2x
Find g[f(-2)]
8
500
Find the constant of variation:
y varies directly as x, y = 9 when x = 54.
1/6
500
Is this drawing a function? (see the board)
No (vertical line test)
500
Length l and width w of a rectangle of given are vary inversely. When the length is 18, the width is 5