| This page was created by a struggling Algebra student. It was designed for other struggling Algebra students. On this page you will learn how to Solve Linear Combinations, use the Substitution Method, and also how to Solve Word Problems. I hope you find all you need! Enjoy, and good luck! |
| How to Solve Linear Combinations: |
3x + 2y = 12 In solving Linear Eqautions, you need to find the variable easiest to cancel out. 6x - 2y = 6 In this paticular problem you would choose Y because it already has the same 9x = 18 numbers and has opposite signs. Once the Y is gone then you have to combine 9x/9 = 18/9 your X's. This would leave you with your X and with you answers which you x = 2 also have to combine. Once they are together you have you division. Divide your 3(2) + 2y = 12 X by your answer and then you have found your X. Your not done yet!! Now 6 + 2y = 12 you have to substitute your answer for X in the place of X in the first problem. 2y = 18 Peice of cake!!! 2y/2 = 18/2 y = 9 |
| How to Use the Substitution
Method: |
5x - 10y = 20 In this type of problem, you use the given variable in place of the variable in the y = 4 + 2x question. If you don't have one given, you can make one you self by rearranging 5x - 10(4 + 2x) = 20 the varaiables. In this question, replace the Y variable with what Y equals. After 5x - 40 - 20x = 20 this, combine like terms and keep only your varaiables on one side and then you -15x = 60 use your basic algebra skills and solve for X. Once you have this you can substi- x = - 4 tute for the Y in the first problem as well. These problems are easy! Don't worry! 5(- 4) - 10y = 20 -20 - 10y = 20 - 10y = - 40 y = 4 |
| How to Solve Word Problems: |
|
A delivery truck arrives at the Roberts’ store with 8 small boxes and 5 large boxes. The total charge for the boxes, without tax or delivery charges, is $184. A large box costs $3 more than a small box. What is the cost of each size box?? 8s + 5l = 184 l = 5 + 3 8s + 5(5 + 3) = 184 8s + 25 + 15 = 184 8s = 104 s = 13 8(13) + 5l = 184 104 + 5l = 184 5l = 80 l = 13 84 |
In this problem you should
look first at the numbers. Seperate them and give them variables. S and L
would fit for small and large. Then you look
for the other problem. Once you see what they are looking for you can easily
set the problem up. Once it is set up it is a substitution problem. Those
are easy so have fun!!!! |