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