Algebra: help, please, w/ systems using substitution

[nakita29]

I have a really weird group of math problems that look like this:

Solve the system of equations using the substitution Method. If the answer is a unique solution, present it as an ordered pair: (x,y). If not, specify whether the answer is "no solution" or "infinitely many solutions".

3x + y = 2
2x - y = 3

The book gives no steps to take to solve, and the teachers answer when asked for help was, "figure it out".
Any help would be great, because this is a college class.
Kita

 

[stapel]

The book gives no steps to take to solve, and the teachers answer when asked for help was, "figure it out".

It is unfortunate that you are being tested over material that has never been taught and which is not included within your textbook. :shock: I hope you're not paying for this course. If you are, you might want to think seriously about filing a complain regarding this behavior.

As for the topic of solving systems of linear equations, using substitution or other methods, there are many great lessons available online, so you can obtain the material which was forbidden to you in your classroom:

. . . . .Google results for "solving systems linear equations"

Have fun!

Eliz.

 

[galactus]

It's called substitution because you solve one equation for a variable and sub into the other. Therefore, creating one equation with one variable which can be solved.

For instance, solve the top equation for y and sub into the second. The second will then be entirely in terms of x. Solve for x and y will follow.