Friday

August 22, 2014

August 22, 2014

Posted by **Jack** on Wednesday, June 20, 2007 at 2:53pm.

I'm currently working on solving algebraic equations with two variables (Example: 3x+4y=9). The computer lesson has taught me nothing but to solve the equation by trial and error -- selecting the proper ordered pair from a multiple choice list after plugging it in to see if it's correct. So, what happens when I don't have a convenient little list of ordered pairs to plug in? Is there a way to solve it from scratch like a one-variable equation?

There is a way to solve this problem from scratch.

You first find a value for either X or Y and then plug that instead of X or Y and solve for the other one.

3X + 4Y = 9

3X = 9 - 4Y

X = (9-4Y)/3

Now plug that instead of X to make it a one variable equation.

3[(9-4Y)/3) + 4Y = 9

That should result as Y=1

Than, plug 1 instead of Y to get X.

3X + 4(1)=9

that should result as X = 5/3

Than, plug the number for both X and Y.

3(5/3) + 4(1)=9

9=9

Hope it helps.

**Related Questions**

Math/ Algebra - Post your responses to the following. Answer each question in a ...

maths-algebra - solve these similtanious equations using an algebraic method 4x+...

quick question regarding equations - I know there are methods out there but what...

Algebra - Translate each problem into a system of equations. DO NOT attempt to ...

algebra attn Reiny - Thanks for your help with the solving of the three ...

algebra 1 - ELEMENTARY ALGEBRA #3 Page 23 Chapter 3 Lesson 3.02 Solving Multi-...

Math - I am really have a tough time trying to solve this problem. I think my ...

Algebra - Solving systems of linear equations in 3 variables... 1) 3x-2y+2z=1 2...

Math coin riddle need help please - I have 56 coins consisting of nickels and ...

algebra - how would i find an equation of a line that goes through points(1,6) ...