Slope and Variation

Slope

100

What is the slope between (3,5) and (4, 9)?

4

200

What is the slope between (3,5) and (-2, 9)?

-4/5

300

What is the slope of the line y = (4/7)x?

4/7

400

What is the slope of a vertical line?

Undefined Slope

500

What is the slope of a horizontal line?

Zero

Direct Variation

100

What is K when x=4 and y=24?

6

200

What is k when x=10 and y = 50?

5

300

When y = 10, x = 5. Find x when y = 8.

4

400

What is the formula for direct variation?

y = Kx

500

What is the value of y? When y= 30, x = 6 so when x = 3, what does y =?

15

Equations

100

Is y = 8x a direct variation? Prove it!
If yes, what is k?

8

200

Is 7y=x a direct variation? Prove it!
If yes, what is k?

y=1/7x

k=1/7

300

Is y=x a direct variation? Prove it!

If yes, what is k?

yes!

k=1

400

Is 6=x/y a direct variation?

If yes, what is k?

yes! y=x/6  or y=1/6x

k=1/6

500

Is x=(y-3)/2 a direct variation?

If so, what is k?

NO.

When I solve for y, y=2x+3

Constant of Variation

100

What is the constant of variation of y = 2/5x?

2/5

200

What is the constant of variation of y = -9/11x

-9/11

300

What is the constant of variation of y = 5/7x?

5/7

400

What is another name for the constant of variation?

Slope, Unit Rate, constant of proportionality, k

500

What is the location of the constant of variation in an equation?

The number in front of the x OR 

k in the y=kx

Challenges!

100

What is the slope of a line that passes through the points (4,6) and (7,6)?

Zero!

200

What is the slope of a line that passes through (6,4) and (6,7)?

Undefined, NOT zero.

300

What is the value of y? A line has a slope of 2. It pass through point (1,2) and (3, y).

6

400

What is the value of x? A line has a slope of 5. It passes through the points (-5,-1 )  and (x,9 ).

-3

500

What is the value of y? A line has a slope of 4/7. It passes through the points ( 2, 4 ) and ( -5,y).   

0