Solving for X...One of the most fundamental algebra concepts.
It’s also one of the most confusing!
Never fear, our very own iD Tech math superhero, Margo, is here to help.
Follow along in this easy tutorial and solving for x will be a snap! Read Margo’s notes and highlights for extra tips and tricks. (you’ll be able to check your work as you go.)
Meet Margo, Math Expert and Operations Manager at iD Tech
Hi there! My name is Margo Berry, and I was a middle school and high school math teacher for five years. I have an expertise in developing Common Core aligned math curriculum, a Master's Degree in Secondary Math Education, and a passion for making math engaging for kids.
Math is all around us! I like to find ways to provide opportunities for my students to interact with math and see it relate to the real world.
Solve for X Math Tutorial
Solving Two Step Equation Word Problems
Dan bought eight new baseball trading cards to add to his collection. The next day, his dog ate half of his collection. There are now only thirty eight cards left. How many cards did Dan start with?
Step One: Highlight important parts of the text
Go through the problem and identify the important pieces. These valuable details usually include all numbers and any indication that something is being added, subtracted, divided, or multiplied.
Step Two: Define your variable(s) or unknowns
The unknown, or what we are trying to solve for is C, or the number of cards Dan started with.
Step Three: Write your equation(s) by breaking down the text of the problem
Next, begin writing the equation by breaking down the important pieces of the problem.
First, Dan bought eight new cards, so we add C+8.
(Here is more on converting word problems into equations.)
Next, because Dan's dog ate half of the collection, we divide everything by 2.
Last, we know that Dan ends up with 38 cards in the end, so we set it equal to 38.
Step Four: Solve your equation!
Now, we are ready to solve! To get C by itself, we must perform inverse operations. In this case, we are dividing C+8 by 2, so we must multiply as the inverse. And then, whatever we do to one side of the equation we must do to the other side of the equation.
After multiplying both sides by 2, we are left with C+8 = 76...meaning we are very close to finding C on its own!
From there, we need to subtract 8 from both sides, ultimately leaving us with our pre-checked answer of C=68!
Step Five: Check your work
To check our work, take the answer of 68 and go through the different operations as described by the important pieces of the word problem.
68 original baseball cards (our answer) + 8 new baseball cards Dan bought = 76 total cards. We know Dan's dog ate half of the collection, so 76 divided by 2 = 38...which is the exact amount of cards the word problem told us Dan was left with!
Step Six: State your final answer
After finding C and checking the work to get there, state the final answer in relation to the main question.
Congratulations! You did it! For more math resources and fun, check out these:
- Fun facts about math
- 2021 math competitions
- Everyday ways to make math fun
- 25 fun math activities
- How to study for a math test
For support, extra help, and challenges in math, iD Tech offers live online math tutoring in algebra, pre-calculus, geometry and more!