Kims Funky Equation

 

Hi my name is kim and I am a student 
at UGHS. I wanted to create a website to help other students learn about 

the substitution method......
      The Substitution Method  :

3x -4y = -15     ;           5x +y = -2
3x - 4(5x -2)=-15    &  -5           -5
3x + 20x + 8 = -15          y = -5x -2
         23x +8 = -15          y = -5(-1)-2
                -8      -8&nbssp;          y = 5-2
             23x  = -23           y = 3
              23        23
                  x  = -1

 Solving The Substitution Method :

1. the first step into solving this equation is to find y by its self first. 
2. afteer you have found the y , you plug the y into the first equation.
3. then you want to multiply 4* -5x and -2 after that you should get 3x + 20x + 8.
4. when you got everything you want to combine the 2 x's and you would get 23x + 8.
5. then you want to sudtract both side by 8 , that would equal 23x = -23.
6. then you slove by dividing by 23 and that would leave x = -1.

 

 
 
I am doing a linear combination table because I want to help other students become better at doing linear combination.
l             LINEAR  COMBINATION:
    5X - 2y = 4                   5x + 2y = 4 
    3x + y = 9                    2(3x + y = 9)
                                             11x  = 22
                                              11       11
                                               x  = 2
   (5x - 2y = 4) 
    (3x + y = 9) 5 
         -11y = -33
         -11      -11
            y  =  3		              Linear combination :

1 . write both equation in the form  Ax + By = C
2 . clear any decimals or fractions.
3 . choose a variable to eliminate.
4 . make the chosen variable's term additive inverses by multiplying one or both equation by a number.
5 . eliminated the variable by adding the equation.
6. substitute to solve for the remaining variable.

 
I picked this word problem to put on this web page because its easier to understand and this is a good word problem to show students how to do it ......
 Word problem !
the measure of one of two supplementary angles is 8 degree more than tree times the other. Find the measure of the larger of the two angles.
 
 

         Sloving Word Problems :

 The first thing you should do is to find out what two supplementary angles equal.
         1.  an supplementary angle is 2 angles added up to equal 180 .
         2.  then next you re-read the equation and you must figuar out what method to use. (you will use the substitution method.) 
         3. after that you would plug it into an equation so the equation would be 
     x + y = 180
and another equation being     y = 8 + 3x
         4. then slove
x + y = 180                              y = 8 + 3x
x + 8 + 3x = 180                       y = 8 + 3(43)
      4x + 8 = 180                       y = 8 + 129
            -8      -8&nbssp;                       y = 137
           4x  =  180
             4        4 
              x =  43