Question

So my math teacher doesn't give us any steps to know how to do the equations. She just tells us the unit, then the vocab plus the essential question. after that she clicks to the next slide and it's just 6 examples then she tells us to do it.
Question: My question is can someone show me the steps to do 2 step equations?

Answer 1

I personally understand what you are saying... everyone has a teacher like that at least once in their schooling.

Doing two-step equations can sometimes be tricky, even if you understand the topic pretty well. All two-step equations are: equations that require two objectives to solve for the variable (That's why it's called a two-step equation).

There are multi-step equations...but let's take one bite at a time.

First, let's establish one simple rule:

Anything you do to one side of the algebraic equation, you must do to the other side for the equation to remain true.

For example:

$2x-4=20$

So, we have this $2x-4$ just chillin' out with the $x$. When trying to solve for a variable, this is usually not what we want. The $x$ needs to be alone for us to know what $x$ equals.

For the first step of getting $x$ alone, we can add $4$ on each side of the equation to cancel out the $-4$ on the variable's side. Remember to do it on both sides of the equation!

$2x-4=20$ becomes $2x-4+4=20+4$

Did you see what I did there? All I did was basically add $4$ to $2x-4$ and $20$. The equation remains equal, but using that simple rule, we were able to get one step closer to isolating the $x$ in the equation.

To continue...

$2x-4+4=20+4$

$2x-4+4$ turns into $2x$ (This is because the $-4$ and the $+4$ cancel out.)

Now we have $2x=24$

This next step should look familiar to you (assuming you already know how to solve for one-step equations, I'll keep it short and sweet).

$2x=24$

Now, since $2x$ is the same as saying $2$ times $x$, we can do the opposite of multiplication...which is division, like so:

$\frac{2x}{2} =\frac{24}{2}$

The $2$'s will cancel each other out and $\frac{24}{2}$ simplifies to $12$.

Awesome! Looks like we solved our two-step equation!

In the equation: $2x-4=20$ , $x=12$

Some things to remember:

1. What ever you do to one side of the equation, you must do to the other.
2. You want to apply the opposite sign of the number you are trying to cancel out of the equation while isolating the $x$.
3. Never make it harder than it needs to be. It is called a two-step equation for a reason, multi-step requires more than two...but wait until you have to work those before you start using fifty different ways to solve the equation.

Hope I was able to help you out! Have a good one, and God bless!

Also, if you are confused about something I answered, or I may be incorrect, feel free to let me know!