Unit 3. System of Equations
0. write a paragraph describing in your own words what this unit was about and what you learned.
In this unit you will find that you are learning about
how you solve equations, such as by graphing. You also learn things as
substitution, elimination and even some word problems
how you solve equations, such as by graphing. You also learn things as
substitution, elimination and even some word problems
1. what is the system of equations why are there 3 types of solutions? explain.
The system of equations is two or more equations. There
are three different types for different reasons.
it all depends on how well you work.
are three different types for different reasons.
it all depends on how well you work.
2. solve by graphing give an example and graph it out.
3. solve by substitution; explain how to do it, give an example and solve it.
y=2x+12
y=4x-24
_________
Step 1: you plug y into
y.
4x-24=
2x+12
Step 2: add 24 to both
sides.
4x-24=2x-12
+24
+24
4x=2x+12
Step 3: get x to one
side.
4x=2x+12
-2 -2
2x=12
Step 4: divide and get x by
itself.
2x=12
___
___
2 2
___ ___
x= 6
y=4x-24
_________
Step 1: you plug y into
y.
4x-24=
2x+12
Step 2: add 24 to both
sides.
4x-24=2x-12
+24
+24
4x=2x+12
Step 3: get x to one
side.
4x=2x+12
-2 -2
2x=12
Step 4: divide and get x by
itself.
2x=12
___
___
2 2
___ ___
x= 6
4. Word Problem: make yout own using two y = mx+b equations and show how to solve it by graphing or substitution.
my brother had two dollars, then had five.
my mom had three dollars, but ended with two.
3x + 2 =
2x = 3
-2x -2x
x+2=3
-2 -2
x = 1
y=2(1)+3
y=2+3
y=5
my mom had three dollars, but ended with two.
3x + 2 =
2x = 3
-2x -2x
x+2=3
-2 -2
x = 1
y=2(1)+3
y=2+3
y=5
5. solve by elimination explain how to do it give an example and solve it.
2x + 11y=
12
-2x - 1y= 8
____________
10y= 20
___
___
10 10
y=2
12
-2x - 1y= 8
____________
10y= 20
___
___
10 10
y=2
6. word problem, make yout own using Ax+By=C equations and show how to solce it using elimination.
Solve for y:
Step
1. Subtract Ax from both sides of the equation to isolate y on left
side
Step
2. Divide by B to both sides of the equation to get y.
Step
1. Subtract Ax from both sides of the equation to isolate y on left
side
Step
2. Divide by B to both sides of the equation to get y.