Direct Variation
Which is a direct Variation Equations? y = 8x + 5 or y = 23x or y = 23x - 10
y = 23x
y = 5x What is the Constant of Variation or Slope?
5
Which Equation Represents a Direct Variation? A. y = 8x B. y = 8x +5 C. y = 8x - 5
A. y = 8x
how to get k or m using a table when it is a Direct Variation.
divide y and x or y/x
quadrants
the four sections on a coordinate plane
x axis
the horizontal number line on a graph
origin
the point (0,0)
direct variation table
the ratio y/x is the same for every pair of points
y axis
the vertical number line on a graph
Ordered Pair or Coordinate Pair
the x and y coordinates used to graph a point
proportion
two ratios set equal to each other
direct variation equation
use the formula: y = kx or y = mx
y = 3x What is the Constant of Variation or Slope?
3
Which method do you use to find out if a table represents a Direct Variation? A. The one in the picture B. Divide each y by the paired x for every coordinate pair in the table.
B. Divide each y by the paired x for every coordinate pair in the table.
Does this table represent a Direct Variation? Explain.
No, All the y/x do not simplify to the same number.
Does this graph represent a Direct Variation? Explain.
No, it is a straight line, it does not go through the origin (0,0).
Does this table represent a Direct Variation? Explain.
Yes. Each y/x simplifies to 1.5
Is this a graph of a Direct Variation? Explain.
Yes. It is a straight line and goes through the origin.
linear
a straight line
direct variation graph
a straight line that goes through the origin