SOLUTION: Equations with two variables: Solve for x and y: 8x + 2y = 7 3x - 4y = 5 Could you please, give me the answer by parts? I will appreciate if you give me the answer, an

Question 170899: Equations with two variables:

Solve for x and y:
8x + 2y = 7
3x - 4y = 5

Could you please, give me the answer by parts? I will appreciate if you give me the answer, and understand the questions by parts, because I need to learn who to resolve this type equations?
thank you for your help. jessica
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
Solve for x and y:
8x + 2y = 7
3x - 4y = 5
:
There are two ways to solve these, elimination and substitution.
Elimination:
You multiply one or both equations so when the equations are added or subtracted, one of the variables is eliminated. Then it is easy to solve for the other variable:
:
Multiply the 1st equation by 2 and you have:
16x + 4y = 14
3x - 4y = 5
----------------Adding will eliminate y:
19x + 0y = 19
or
19x = 19
x =
x = 1
:
Now substitute 1 for x in one of the original equations, we'll use the 1st one.
8(1) + 2y = 7
8 + 2y = 7
2y = 7 - 8; subtracted 8 from both sides
2y = -1
y =
:
Check solutions by substituting both solutions in the 2nd original equation.
3(1) - 4(-1/2) = 5
3 + 2 = 5; remember minus a minus is a plus
:
Did this help you understand these problems?
RELATED QUESTIONS
6.1 I. Solve each system by graphing, and classify the system as dependent or... (answered by Flake)

could you please help me with a couple of problems? These are systems of equations(2 by... (answered by stanbon)

How do you solve for x and y, and then graph these equations? 8x + 2y = 7 3x - 4y =... (answered by Fombitz)

Hi can you please help me in solving these equations thank you 1.what are the values... (answered by dolly)

If you could please help me I have four equations that i have to solve for w, x, y, and... (answered by stanbon)

Please help!!! I don't understand any of this. Any assistance you can provide will be... (answered by funmath)

Hello can you please answer a few questions? My teachers wants me to solve Linear... (answered by solver91311)

I need to solve the following system of linear equations with three variables. Here is... (answered by ptaylor)

I've missed a lot of school because I've been sick and I'm trying to get all of my work... (answered by jsmallt9)