Chapter 5

what formula is this y2-y1=m(x2-x2)

point slope form

given two point write on equation that goes through (1,-4) (3,2) whats the second step

use the slope and one point; pick the easier point

solve for point slope form slope=0; (3,-4)

y+4=0(x-3)

solve for point slope form slope= 5/2; (-3,0)

y-0=5/2(x+3)

solve for point slope form slope= 2; (1/2,1)

y-1=2(x+1/2)

the value of y varies directly with x. y=4.5 when x=0.5 find y when x=10

y=90

do these points form a direct variation (1,6) (3,18) (5,30)

yes each has the same value of k. do these points are part of a direct variation

solve to see if this is a direct variation -3x+5y=0

yes k=3/5x

is this a direct variation and if so name the constant variation. y=4x

yes k=4

what indicates that the pints would form a direct variation?

all the k are the same

what does this represent in direct variation? k

constant of variation

what is this formula? y=kx

direct variation

the value of y varies directly with x, and y=6 when x=12. find y when x=27? whats the first step you take

find k for the for the first point given k=y/x

given two point write on equation that goes through (1,-4) (3,2) whats the third step

find point slope form then slope intercept form

when graphing slope intercept form how do you decide to rise or fall when graphing the 2nd and 3rd point

if the slope is positive or negotive

what letter represents slope of the line

m

whats the first thing you do when graphing slope intercept form

marking a point at the y intercept

solve to see if this is a direct variation 2x+y=10

no it is not a direct varation

do these points form a direct variation (2,-2) (4,0) (8,4)

no these points arent direct variation

what formula is this? y=mx+b

slope intercept form

if an equation can be rewritten in the form y=kx, it is a direct variation equation

solve for y

the value of y varies directly with x, and y=6 when x=12. find y when x=27? whats the second step

use k, x from 2nd point given to solve for y y=kx

what formula would you use to see if a set of point would create a direct variation.

y/x=k

graphy for point slope form graph y-2=1/2(x-3)

.

graph y=-3x+2 whats the slope (1) whats the rise/fall over run (2) where do you put the first point (3)

1 -3 2 -3/1 fall/run 3 +2

given two point write on equation that goes through (1,-4) (3,2) whats the first step

find the slope by using slope formula

what is the second thing you do when graphing slope intercept form

follow the slope and mark a 2nd and 3rd point

what letter represents y intercepts

b