Assignment #62 – Solving Systems Algebraically
Name: ______________________
Class: __________________
M8-U5: Notes #3 – Solving Systems Algebraically – set them equal
Date: __________________
Graph the following system of equations, find the solution.
y  x  3

y  x  5
1.
 y  2x  6

y  x  3
2.
y
–6
–5
–4
–3
–2
y
6
6
5
5
4
4
3
3
2
2
1
1
–1
–1
1
2
3
4
5
6
x
–6
–5
–4
–3
–2
–1
–1
–2
–2
–3
–3
–4
–4
–5
–5
–6
–6
1
2
Now let’s look at the algebra of setting the two equations equal to each other.
1.
y  x  3

y  x  5
2.
1
 y  2x  6

y  x  3
3
4
5
6
x
Assignment #62 – Solving Systems Algebraically
Try It!
a.
 y  3x  30

 y   x  14
b.
y  7x  4

 y  9x  6
Word Problems
Example 3: Deborah has two paintings in her portfolio and paints three more each week.
Kai has twelve paintings in her portfolio and paints two more each week. After how
many weeks will Deborah and Kai have the same number of paintings?
2
Assignment #62 – Solving Systems Algebraically
Try It!
Trey’s online music club charges a monthly rate of $20 plus $0.80 per song download.
Deb’s online music club charges a monthly rate of $21 plus $0.60 per song download.
For what number of songs will the monthly charge be the same for both clubs? How
much will it cost?
Practice:
1.
 y  22 x  4

 y  14 x  36
2.
3
 y   x  16

 y  7 x  8
Assignment #62 – Solving Systems Algebraically
Name: ______________________
Class: __________________
M8-U5: HW #3 – Solving Systems Algebraically – set them equal
Date: __________________
Graph the following system of equations, find the solution.
y  x 1

 y  x  3
1.
 y  4x  6
2. 
 y  2x  2
y
–6
–5
–4
–3
–2
y
6
6
5
5
4
4
3
3
2
2
1
1
–1
–1
1
2
3
4
5
6
x
–6
–5
–4
–3
–2
–1
–1
–2
–2
–3
–3
–4
–4
–5
–5
–6
–6
Confirm the same answers algebraically.
1.
y  x 1

 y  x  3
 y  4x  6
2. 
 y  2x  2
4
1
2
3
4
5
6
x
Assignment #62 – Solving Systems Algebraically
Solve the following systems algebraically. Hint: set them equal and solve for x.
3.
 y  5 x  8

 y  2 x  7
4.
 y  22 x  4

 y  14 x  28
5.
Suppose a video store charges nonmembers $4 to rent each video. A store
membership costs $21 and members pay only $2.50 to rent each video. For what
number of videos is the cost the same?
6.
Suppose your club is selling candles to raise money. It costs $100 to rent a booth
from which to sell the candles. If the candles cost your club $1 each and are sold
for $5 each, how many candles must be sold to equal your expenses?
5
Assignment #62 – Solving Systems Algebraically
Spiral:
7.
Jane’s cell phone plan is $40 per month plus $0.15 per minute for each minute
over 200 minutes of call time. If Jane’s cell phone bill is $58.00, for how many
extra calling minutes was she billed?
Evaluate the following expressions:
1
ab 3 , where a  and b  2
8.
4
10.
a.
9.
Multiple Choice:
Which is a table of values for y  x  6 ?
b.
c.
6
2 
4 3
d.