Warm up: Do this on the page you will take notes on today Warm up: Do this on the page you will take notes on today! What are the three methods to solving a system of linear equations listed in the “All I Do is Solve” lyrics? 1.) Graphing 2.) Elimination 3.) Substitution 4.) Matrix
Solving Systems by Substitution Aka “The Blob” method! I will be able to solve a system of equations using the substitution method.
Pay Close Attention If you don’t take detailed notes you will have no idea what to do and will get freaking nuke towned destroyed!
Step 1: Find an equation that looks like: x=_______ or y=______ If you don’t have one, you have to solve for one
Step 2: Circle everything after the equal sign. x=_______ or y=______ This is called “The Blob”
Step 3: Substitute “the blob” Plug “the blob” into the other equation for the variable it equals. “Like a chord in a socket!”
Step 4: Solve the equation Get the variable by its self
Step 5: Substitute your answer from step 4 into the “the blob” and solve Plug your lonely variable into “the blob” “Like a chord in a socket!”
Step 6: Write your answer as an ordered pair (x,y) Example: if x= 7 and y=4 write (7,4) We call this “The Solution” and it is where our 2 linear equations would intersect on a graph!
Step 1: Find an equation that looks like: x=____ or y=_____ Step 2: Circle everything after the equal sign. Step 3: Substitute “the blob” Step 1: Find an equation that looks like: x=____ or y=_____ y=4x+2 3x+y=9
y=4x+2 3x+(4x+2)=9 Step 4: Solve the equation Step 3: Substitute “the blob” y=4x+2 3x+(4x+2)=9
y=4x+2 3x+4x+2=9 7x+2=9 7x=7 x=1 Step 4: Solve the equation Step 5: Substitute your answer from step 4 into the “the blob” and solve y=4x+2 3x+4x+2=9 7x+2=9 7x=7 x=1
y=4(1)+2 y=4+2 y=6 So, x=1 and y=6 (1,6) Step 6: Write your answer as (x,y) Step 5: Substitute your answer from step 4 into the “the blob” and solve y=4(1)+2 y=4+2 y=6 So, x=1 and y=6 (1,6)
Example 2 3y+4x=10 2y+x=5
Your Turn Whiteboard Find the Solution 4x+3y=10 y=2x+3
Find the Solution 7x+5y=6 x=4y+3
Find the Solution 2x+3y=10 2x-y=4