Download any ordered pair (point) that makes ALL the equations

Objective: Solving systems of linear equations
by graphing
System of
linear
equation
solution
How do I
solve linear
systems of
equations?
two or more linear equations
any ordered pair (point) that makes ALL the
equations true
1. graph the equations
2. Find the point of intersection
*** point of intersection is a solution ***
example
Graph the following equations and find the solution.
Check your answer.
y x5
y  4 x
y  mx  b
y x5
1
m b5
1
y  mx  b
y  4 x
4
m
b0
1
Objective: Solving systems of linear equations
by graphing (real-world problems)
How do I
solve
problems
using linear
systems of
equations?
1. Define variables
2. Write equations
3. Graph equations
4. Find solution
example
Suppose you have $55 in your bank account. You start
saving $10 each week. Your friend has $20 in her bank
account and is saving $15 each week. When will you and
your friend have the same amount of money in your
accounts?
STEP 1
define variables
Let w = time for accounts to be equal
Let z = money account
example
Suppose you have $55 in your bank account. You start
saving $10 each week. Your friend has $20 in her bank
account and is saving $15 each week. When will you and
your friend have the same amount of money in your
accounts?
STEP 2
Write equations
z  10 w  55
z  15 w  20
your account
friend’s account
STEP 3
Graph equations
z  10 w  55
z  15 w  20
Solution: 7 weeks