Algebra

It does, thanks.

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.

1. 👍 0
2. 👎 0
3. 👁 98

Similar Questions

1. Math/ Algebra

Post your responses to the following. Answer each question in a separate paragraph: Techniques that can simplify solving equations and inequalities are to clear fractions and decimals when solving linear equations and

asked by Amanda on June 14, 2010
2. algebra attn Reiny

Thanks for your help with the solving of the three equations! Yes, it was a typo. I just finished solving it a long way, solving for the 1st 2 equations then the 2nd and 3rd and plugging in variables...etc. etc. Your way gave the

asked by Terri on February 24, 2009
3. quick question regarding equations

I know there are methods out there but what do you think is the best or easiest method(s) of solving a system of equations. Depends on the coefficients of the equation. If in one of the equations I can solve for one of the

asked by Shawn on August 14, 2007
4. to annonymus can you help me with math

How do i solve inequalitites with three variables. I still can't figure it outplease help. x+y=1 y-z=-3 2x+3y+z=1 the answers are 3,-2,1 how do get there by solving linear equations with three variables. 5x-2y-z=2 -y+2z=11

asked by Jasmine202005 on October 22, 2006
5. Math

PLEASE CHACK MY ANSWER!!! Discussion for Applications of Linear Systems When solving a system of equations, how do you determine which method to use? My answer: I determine which method to use by looking at the equations. If both

asked by Matthew on December 15, 2016
6. algebra

Explain the difference between solving a system of equations by the algebraic method and the graphical method. Someone also wants to know why there are different methods for solving the same problem-what would you tell him?

asked by kiMBERLY on July 12, 2010
7. Equations and variables

Why are variables and equations such an important part of algebraic reasoning?

asked by Sarah on March 26, 2008
8. math

what is.7 of 39.4????? 39.4*.7=27.58 Having trouble solving equations with two variables..both unknown

asked by Caitlyn on March 20, 2007
9. Algebra

Solving systems of linear equations in 3 variables... 1) 3x-2y+2z=1 2) 2x+5y-5z=7 3) 4x-3y+z=-3 I combined 1 and 3 to get -5x+4y=7 And then i combined 2 and 3 to get -13y+11z=-17. Can that be right? how would you combine those two

asked by Max on November 13, 2010
10. Physics

You are given vectors A = 5.0i - 6.5j and B = -2.5i + 7.0j. A third vector C lies in the xy-plane. Vector C is perpendicular to vector A and the scalar product of C with B is 15.0. Find the x and y components to vector C. Here's

asked by Vectors on August 30, 2014

More Similar Questions