Chapter 6

advertisement
Name:
Date:
Period:
Systems of Equations & Inequalities
Solving by Graphing/Solving by Substitution/ Solving by Elimination/
Solving Special Systems/ Solving Linear Inequalities/ Solving Systems
of Linear Inequalities
Lessons: 6.1-6.6
Packet 6
Tennessee State Standard
SPI 3102.3.9 Solve
systems of linear
equation/inequalities
in two variables.
Common Core State Standards
A.CED. 2. Create equations in two or more variables to
represent relationships between quantities; graph
equations on coordinate axes with labels and scales.
A.CED. 3. Represent constraints by equations or
inequalities, and by systems of equations and/or
inequalities, and interpret solutions as viable or
nonviable options in a modeling context. For example,
represent inequalities describing nutritional and cost
constraints on combinations of different foods.
A.REI. 5. Prove that, given a system of two equations
in two variables, replacing one equation by the sum of
that equation and a multiple of the other produces a
system with the same solutions.
A.REI. 6. Solve systems of linear equations exactly and
approximately (e.g., with graphs), focusing on pairs of
linear equations in two variables.
A.REI. 12. Graph the solutions to a linear inequality in
two variables as a half-plane (excluding the boundary
in the case of a strict inequality), and graph the solution
set to a system of linear inequalities in two variables as
the intersection of the corresponding half-planes.
1
Name:
Date:
Lesson Covered 6-1
Objective: TSW solve systems of
linear equations by graphing
Period:
Skills Covered: graphing linear
equations, identifying coordinates
Systems of Equations and
Inequalities
Vocabulary
A system of linear equations is __________________________________________________________
_________________________________. A solution of a system of linear equations with two variables is
_________________________________________________________________________________.
Special Note: If the lines are parallel, there is NO SOLUTION to the system. If the lines are on top of each
other (in other words, they are the same line), then EVERY POINT on the line is a solution to the system.
Example 1. Tell whether
the ordered pair (6, -1) is a
solution of the system:
1
𝑦 = 3𝑥 − 3
[
6𝑥 + 3𝑦 = 12
Example 2. Solve the system by graphing. Check your answer.
3𝑥 + 𝑦 = −8
[
−2𝑥 − 𝑦 = 6
a) Put both lines in slope-intercept form.
b) Graph. Use graph paper and a straight edge. BE PRECISE!
c) Find point of intersection.
Solution always written as ordered pair: ( ___ , ___ )
2
Name:
Lesson Covered: 6-1
Objective: TSW solve systems of
linear equations by graphing
Date:
Skills Covered: graphing linear
equations, identifying coordinates
Period:
Systems of Equations and
Inequalities
TO SOLVE ON CALCULATOR: After writing both equations in slope-intercept form, push Y= , put the 1st
equation in Y1 and the 2nd equation in Y2. Press 2nd TRACE (which is CALC), go to 5:intersect, move the
left or right arrows until you are close to the point of intersection, then press ENTER 3 times. At the
bottom of the screen the calculator will display the intersection.
Part A.
1. Is the ordered pair (-2, 1) a
solution of the system:
2𝑥 − 3𝑦 = −7
?
[
3𝑥 + 𝑦 = −5
2. Solve the system by graphing:
−1𝑥 + 12𝑦 = 3
.
[ 2
2𝑥 + 3𝑦 = 13
5. Solve the system by graphing:
𝑥 − 2𝑦 = 4
.
[
3𝑥 + 𝑦 = 5
3. Use a graphing
calculator to graph and
solve the system.
−18𝑥 + 6𝑦 = 4
[
𝑦 = −3.2𝑥 + 2.7
6. To deliver mulch,
Lawn & Garden
charges $30 per cubic
yard plus a $30
delivery fee. Yard
Depot charges $25 per
cubic yard plus a $55
delivery fee. For how
many cubic yards of
mulch will the cost be
the same? What will
that cost be?
3
Name:
Lesson Covered: 6-1
Objective: TSW solve systems of
linear equations by graphing
Date:
Skills Covered: graphing linear
equations, identifying coordinates
Period:
Systems of Equations and
Inequalities
Part B.
1. Is the ordered pair (1, -4) a
solution of the system:
𝑥 − 2𝑦 = 8
?
[
4𝑥 − 𝑦 = 8
5. Solve the system by graphing:
𝑦 = 12𝑥
.
[
𝑥 + 𝑦 = −1
2. Solve the system by graphing:
−2𝑥 − 1 = 𝑦
.
[
𝑥 = −𝑦 + 3
3. Use a graphing
calculator to graph and
solve the system. Round
your answer to the
nearest tenth.
8
5
𝑥+𝑦 =9
3
[
5
2
𝑦 = 4𝑥 − 3
6. The baseball
team is selling hats.
They contacted two
companies. Hats Off
charges a $50 design
fee and $5 per hat.
Top Stuff charges a
$25 design fee and
$6 per hat. A) For
how many hats will
the cost be the
same? B) What is
that cost? C) Explain
when it is cheaper
for the team to use Top Stuff and when it is cheaper to use Hats
Off.
4
Name:
Lesson Covered: 6-2
TSW solve systems of
equations using substitution
Date:
Skills Covered: solving equations
Period:
Systems of Equations and
Inequalities
More Practice!
1. [
𝑥 − 2𝑦 = 4
𝑥 + 8𝑦 = 16
4𝑥 = 𝑦 − 1
4. [
6𝑥 − 2𝑦 = −3
2. [
2𝑥 + 𝑦 = −4
𝑥 + 𝑦 = −7
5. [
4𝑦 − 5𝑥 = 9
𝑥 − 4𝑦 = 11
5
3. [
𝑦 =𝑥+3
𝑦 = 2𝑥 + 5
6. One cable TV provider has a $60
setup fee and charges $80 per
month, and another provider has a
$160 equipment fee and charges $70
per month. A) In how many months
will the cost be the same? What will
that cost be? B) If you plan to move
in 6 months, which is the cheaper
option? Explain.
Name:
Lesson Covered: 6-2
TSW solve systems of
equations using substitution
Date:
Period:
Skills Covered: solving equations
Systems of Equations and
Inequalities
Guess what? More Practice
𝑥 + 2𝑦 = 8
𝑥 + 3𝑦 = 12
2. [
𝑦 = 1.2𝑥 − 4
2.2𝑥 − 𝑦 = −5
5. [
1. [
4. [
𝑥 = 7 − 2𝑦
7. [
2𝑥 + 𝑦 = 5
–𝑥 + 𝑦 = 4
3𝑥 − 2𝑦 = −7
𝑥 + 2𝑦 = −1
4𝑥 − 4𝑦 = 20
1
2
𝑥 + 13𝑦 = 6
8. [
𝑥−𝑦 =2
6
3. [
6. [
3𝑥 − 𝑦 = 11
5𝑦 − 7𝑥 = 1
2𝑥 + 2𝑦 = 2
−4𝑥 + 4𝑦 = 12
9. A jar contains n nickels and d
dimes. There are 20 coins in the jar,
and the total value of the coins is
$1.40. How many nickels and how
many dimes are in the jar?
Name:
Date:
Lesson Covered 6-4
Objective: TSW classify systems of
linear equations and determine the
number of solutions.
Period:
Skills Covered: solving equations
for a variable and graphing lines
Systems of Equations and
Inequalities
Classify each system. Determine the number of solutions.
𝑦 = −2𝑥 + 5
Example 1. [
2𝑥 + 𝑦 = 1
𝑦 =𝑥−3
Example 2. [
𝑥−𝑦−3=0
Example 3. [
−7𝑥 + 𝑦 = −2
7𝑥 − 𝑦 = 2
Example 4. [
7
3𝑥 + 𝑦 = 2
3𝑥 − 𝑦 = 0
Name:
Date:
Lesson Covered 6-4
Objective: TSW classify systems of
linear equations and determine the
number of solutions.
Skills Covered: solving equations
for a variable and graphing lines
Period:
Systems of Equations and
Inequalities
Part B: Classify each system. Determine the number of solutions.
1. [
4. [
2𝑥 − 𝑦 = 3
6𝑥 − 3𝑦 = 9
𝑥 + 2𝑦 = −4
𝑦 = −12𝑥 − 4
7. [
𝑦 = −𝑥 + 5
𝑥+𝑦 =5
2. [
5. [
𝑦 = 2𝑥
𝑥 + 𝑦 = −6
−9𝑥 − 3𝑦 = −18
3𝑥 + 𝑦 = 6
3. [
𝑦 − 1 = 2𝑥
𝑦 = 2𝑥 − 1
6. Matt has $100 in a checking
account and deposits $20 per
month. Ben has $80 in a checking
account and deposits $30 per
month. Will the accounts ever
have the same balance? Explain.
8. The pep club is selling team buttons. Buttons, Inc. charges $50 plus
$1.10 per button, and Logos charges $40 plus $1.10 per button. Write
an equation for each company’s cost. Find when the price for both
companies is the same. What part of the equation should the pep club
negotiate to change so that the cost of Buttons, Inc. is the same as
Logos? What part of the equation should change in order to get a
better price?
8
Name:
Date:
Lessons Covered 6-5,6-6
Objective: TSW graph and solve
linear inequalities and systems of
linear inequalities in 2 variables.
Skills Covered: solving equations
for a variable and graphing lines
Period:
Systems of Equations and
Inequalities
For a system the solution is the half-plane where the shading intersect.
Example: Graph the solutions of the inequality: 2𝑥 + 4𝑦 ≤ 8.
Solve for y:
Solid Line or Dotted Line?
Shade Above or Below?
𝑦<
3
𝑥
4
+1
[
2𝑥 + 3𝑦 ≥ 15
]
−7𝑥 − 4𝑦 ≥ 20
9
Name:
Date:
Lessons Covered 6-5,6-6
Objective: TSW graph and solve linear
inequalities and systems of linear
inequalities in 2 variables.
Skills Covered: solving equations for a
variable and graphing lines
Period:
Systems of Equations and Inequalities
Part A. Graph each system of linear inequalities.
1. [
𝑦 < 2𝑥 − 1
𝑦>2
2. [
𝑦 ≥ 3𝑥
3𝑥 + 𝑦 ≥ 3
𝑥<3
𝑦 >𝑥−2
5. [
𝑥+𝑦 ≤3
𝑦 > 3𝑥 − 4
4. [
10
Name:
Date:
Lessons Covered 6-5,6-6
Objective: TSW graph and solve linear
inequalities and systems of linear
inequalities in 2 variables.
Period:
Skills Covered: solving equations for a
variable and graphing lines
Systems of Equations and Inequalities
Part B. Graph each system of linear inequalities.
1. [
𝑦+𝑥 >2
𝑦 ≤ −3𝑥 + 4
4. [
𝑦 ≤ −3𝑥 − 1
𝑦 ≥ −3𝑥 + 1
2. [
𝑥 + 5𝑦 > −10
𝑥−𝑦 <4
5. [
11
𝑦 >𝑥−2
𝑦≤3
Name:
Date:
12
Period:
Download