Day 10 Review ch.5.notebook
5.2 Direct Variation
October 17, 2016
Suppose y varies directly with x, and y = 35 and x = 5.
What direct variation equation relates x and y? What is
the value of y when x = 9?
Step 1:
y = kx
Step 2:
35 = k(5)
y = 7(9)
y = 63
7 = k
y = 7x
Oct 5­11:50 AM
Suppose y varies directly with x, and y = 10 and x = ­2.
What direct variation equation relates x and y? What is
the value of y when x = ­15?
Oct 5­1:06 PM
The price you pay varies directly with the number of pencils you buy. Suppose you buy 3 pencils for $0.51. How much does each pencil cost? Write a direct variation equation.
Oct 7­10:40 AM
Review Ch.5
1.
Oct 7­10:53 AM
2. Find the slope of the line contain the points (‐2, 12) (‐9, ‐2). 3. Write the equation of the line in slope intercept form.
Oct 16­1:19 PM
Oct 16­1:14 PM
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Day 10 Review ch.5.notebook
October 17, 2016
6. Write the function that defines this table.
4.
5. Write the function that defines this table.
Oct 16­1:14 PM
Oct 16­1:33 PM
Using the relation {(­5, ­39), (­1, ­9), (0, 1), (2, 5), (10, 21)}
9. Write the equation in slope­intercept form. 7. Determine the average rate of change.
m = ­¾ ; (4, 1)
8. Write the equation in slope intercept form.
Oct 16­1:22 PM
10.
Oct 16­1:36 PM
Use the line that passes through ( 3, 0) and (7 , -2).
11. Find the slope.
12. Write the equation of the line in point-slope form.
13. Write the equation of the line in slope intercept form.
14. Write the equation in standard form.
Oct 16­1:12 PM
Oct 16­1:39 PM
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Day 10 Review ch.5.notebook
October 17, 2016
Graph each equation.
Give the slope of each equation.
15.
x = -4
16.
16. Write a direct variation equation that relates x and y when y = 10 and x = 4.
y=3
17. Find the value of y when x = 12.
Nov 17­7:14 AM
Oct 16­1:41 PM
19. Graph the equation.
18.
2x + 4y = 8
20. What is the x-intercept?
21. What is the y-intercept?
Oct 16­1:14 PM
22.
Nov 17­7:14 AM
23.
Oct 16­1:13 PM
Oct 16­1:22 PM
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Day 10 Review ch.5.notebook
October 17, 2016
25.
24. Graph
Write the equation of the line in slope­intercept form.
y = -x + 5
y < -x + 5
a) parallel to y = 4x ­ 1 passing through (4, 10)
b) perpendicular to y = 4x ­ 1 passing through (4, 10)
Mar 11­1:00 PM
Oct 14­3:03 PM
Classwork:
p.354 #6 - 14, 18 - 26 even
#22, 24 on graph paper
Homework: Study for test.
Oct 16­2:02 PM
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