Slope
Direct Variation
Equations
Constant of Variation
Challenges!
100
What is the slope between (3,5) and (4, 9)?
4
100
What is K when x=4 and y=24?
6
100

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

8

100
What is the constant of variation of y = 2/5x?
2/5
100

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

Zero!

200
What is the slope between (3,5) and (-2, 9)?
4/-5
200
What is k when x=10 and y = 50?
5
200

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

y=1/7x

k=1/7

200
What is the constant of variation of y = -9/11x
-9/11
200

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

Undefined, NOT zero.

300
What is the slope of the line y = 4/7x?
4/7
300
What is the value of x when y = 10, x = 5. Find x when y = 8.
4
300

Is y=x a direct variation? Prove it!

If yes, what is k?

yes!

k=1

300
What is the constant of variation of y = 5/7x?
5/7
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 slope of a vertical line?

Undefined Slope

400
What is the formula for direct variation?
y = Kx
400

Is 6=x/y a direct variation?

If yes, what is k?

yes! y=x/6  or y=1/6x

k=1/6

400

What is another name for the constant of variation?

Slope, Unit Rate, constant of proportionality, k

400

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

-17/5

500
What is the slope of a horizontal line?
Zero
500
What is the value of y? When y= 30, x = 6 so when x = 3, what does y =?
15
500

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

If so, what is k?

NO.

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

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

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

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