Lesson Algebra: How to Solve a Elimination Equation

Source code of 'Algebra: How to Solve a Elimination Equation'

This Lesson (Algebra: How to Solve a Elimination Equation) was created by by Tobiasz(54)

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About Tobiasz: I like to read and help pther people with there problems!

Thank you for visiting this lesson.

ok first we need a equation.

4x + 2y = -10
 2x + 3y = 33

First we need to find out, which variable we want to find. Don't use the harder one to look smart because faster is better. So in this case we are going to eliminate {{{x}}} because its easier.

A.) 4x + 2y = -10
  B.)  2x + 3y = 33       We need both {{{x}}} to have the same number, so lets multiply -2 to the
                          B equation.

4x + 2y = -10
 -2(2x + 3y = 33)

4x + 2y = -10
 -4x - 6y = -66          Now We can eliminate 4x!
-----------------

now we have

-4y = -66

Divide Both sides by 4 and you recieve

{{{y = 16}}}

Now lets plug this in and solve to find y and check the equation later.

Lets use a easy equation To solve for y.

Lets use Equation B.

2x + 3y = 33

2x + 3(16) = 33

2x + 48 = 33  <--- minus 48 from 48 and 33

2x = -15

{{{x = -7.5}}} Lets Check if its correct. OR not. =]

2x + 3y = 33

2(-7.5) + 3(16) = 33

-15 + 48 = 33

{{{33 = 33}}}

Correct, its correct.

Thanks again, and try the way i showed, =]