Direct Variation
The value of y varies directly with x. If x = 8, then y = 2. What is the value of y when x = 12?
y = 3
a. The rate of change is positive
c. The rate of change is 2
f(x) = 13.6x + 3.7, what is the y-intercept?
y-intercept is 3.7
What is the value of f(x) = 23.2x + 2.5 at x = −4.2?
−94.94
These are lines that will intersect at a 90° angle
Perpendicular lines
The value of y varies directly with x. If x = 12, then y = 144. What is the value of y when x = 32?
y = 384
Using question 5 on your review...
The water level ______________
at a rate of _______ meters/hour
The water level _decreases_
at a rate of _2_ meters/hour
a) y = 3x+4
Books at the book fair cost $8.99 per book. The book company charges a flat fee of $2.99 no matter how many books you buy.
How much is the total cost for 56 books?
$506.43
What is the equation, in point-slope form, of a line that crosses the x-axis at 4 and is parallel to the line
y = 2x - 4
y - 0 = 2 (x - 4) or y = 2 (x - 4)
The value of y varies directly with x. If x = 15, then y = 75. What is the value of x when y = 500?
x = 100
Using question 7 on your review:
A function has a y intercept of 3 and an x intercept of 1 Which graph below matches this description?
the first graph
f(x) = 13.6x + 3.7, what is the value of f(6.2)?
f(6.2) = 88.02
What is the slope of the line represented by
18x + 6y = 36
rate of change, or slope, is m = -3
Given a transformation of f(x) into
g(x) = 2*f(x) - 4, what direction and how many units is it vertically translated?
It is vertically translated down 4 units
The value of y varies directly with x. If x = 56, then y = 7. What is the value of x when y = 8?
x = 64
On question 4 of your review:
What is the equation and slope of the graph?
b. y = -3, slope is 0
Given the point-slope form equation:
y - 5 = 1/3 (x+6)
rewrite it as a slope-intercept form equation, i.e.
y = mx + b
y = 1/3 x + 7
What is the y-intercept of the line represented by
18x + 6y = 36
Given a transformation of f(x) into
g(x) = 2*f(x) - 4, what is the dilation factor and will it make this steeper graph?
Dilation factor of 2, and it will make a steeper graph
The value of y varies directly with x. If x = 8, then y = 96. What is the value of x when y = 168?
14
Using question 9 on your review:
Show me the correct graph for the transformation of f(x),
g(x) = 2f(x) - 3
Show me your paper...
y = 1/4x +12, what is the x-intercept?
x = -48 or (-48,0)
Use point-slope form to write an equation with the given information. Then, rewrite the equation in slope-intercept form.
The slope is 1/3 The point (–6, 5) lies on the line.
y = 1/3 x + 7
What is the equation, in slope intercept form, of a line that crosses the x-axis at 6 and is perpendicular to the line: y = 1/3x - 2?
y = -3x + 18