This week in math we worked on learning terms like elimination and substitution.
Here is an example of elimination.
Here is our 2 equations and we are asked to use the method of elimination to figure out our missing variables which in this case are a and b.
Our first step we want to do is figure out which variable we will eliminate first. In this case i just chose A to start with.
In order to use the method of elimination we have to cancel out one of our variables in both equations and in order to do that u have to have one negative and one positive which is why i multiply the A with negative 2. I cant just multiply the A though, you need to multiply everything in the equation.
In the picture above i multiplied everything by -2 like i said we do, then i cancelled out our “like” variables by adding them together and then all that’s left was to add the other variables and simply which in our case we divided our answer by 7 on both ends leaving us with b=2.
We aren’t done there though, we still need to figure out what our variable “A” is. In order to do this all we need to do is plug 2 in wherever we see b.
In the image above i plugged 2 in wherever i saw B and then simply solved which left us with an answer of A=3.