A "system" of equations is 2 equations where the x's in each equation equal the same number, and the y's in each equation equal the same number.

When you find what x and y equal, they are written in parentheses as an ordered pair like this: (-3, 5) with the x always being written before the y. If you graph the (-3, 5) -- use the slope-intercept form "rise over run" -- that is where the two graphed equations (lines on the graph) would intersect.

►After graphing, if lines are parallel they will not intersect. The answer to this kind of problem is "

*no solution*." There is no point on the graph at which the lines will intersect.

►If the lines end up graphing as the same line, on top of one another, the answer is "

*infinite solutions*" or "

*entire line*." In other words, ANY of the points on the entire line will work in both of the systems of equations.

►If the lines

**do**intersect, the point at which they intersect is your answer. You will write the answer as an ordered pair, such as (-2, 5).

A.

__Solving Systems of Equations by Graphing__(1) Solving Systems by Graphing (YayMath.org -

*my favorite math videos!*)

►Accompanying worksheet for this video.

(2) Solving Systems by

**Graphing**

(3) Solving Systems by

**Graphing**[y-intercept (b) is zero]

B.

__Solving Systems of Equations by Substitution__

(4) YourTeacher.com - Solving Systems by

**Substitution**

(5) YayMath.org - Solving Systems by

**Substitution**

►Accompanying worksheet for this video (only do the Substitution method problems for now).

C.

__Solving Systems of Equations by Elimination__

(6) YayMath.org - Solving Systems by

**Elimination/addition.**

►Accompanying worksheet for this video.

"To 'eliminate' may make you think of the Terminator. But in Algebra, it's a method of solving two or more equations at the same time." ~Yay Math!

(7) YayMath.org - Solving Systems by

**Elimination/addition.**

►Accompanying worksheet for this video (use the last problem -- this is the rest of the video from #5 above). Full video here.

Thanks for posting these! I haven't heard of "Yay math" & this is perfect for what I needed! I've been using your physical science resources all year, & now I'll be using you for Algebra, too! THANK YOU!

ReplyDeleteYou're welcome, Dana! Don't you just love Physical Science? =)

ReplyDeleteI haven't posted much algebra, so maybe you can find what else you need at YayMath, or from some of the other youtube users I've posted. =)

God bless you in your studies!