What does solve for x mean?

To solve for x means to find the number that x stands for, the one that makes both sides of the equation equal. In x + 6 = 7, x is 1, because 1 + 6 = 7 and no other number works. You reach it by undoing what was done to x, step by step, until one side reads just x.

How do you solve equations with x on both sides?

Gather the x terms on one side and the plain numbers on the other, then solve what is left. Take 9x + 4 = 3x + 34. Subtracting 3x from both sides gives 6x + 4 = 34, and subtracting 4 gives 6x = 30. Since 6 × 5 = 30, x = 5. Put 5 back in, and both sides come to 49.

How do you remember which step undoes which?

Think of the operations as partners: adding and subtracting undo each other, multiplying and dividing undo each other, and a square root undoes squaring. Undo the last thing done to x first. In 4x + 7 = 31, the 7 was added last, so take it away first to get 4x = 24. Then divide by 4, and x = 6.

Why does my child find letters in equations confusing?

Letters feel strange at first because, until algebra, every symbol in a calculation stood for a number you could see. Call x a secret number instead, and start with equations your child can guess, such as x + 5 = 12. Once guessing gets slow on bigger equations, the undoing steps start to feel like a shortcut rather than a rule.

What does this algebra equation game cost a school, and how does it fit a lesson?

Nothing: every equation level is free for a class and opens in a browser on school laptops or tablets, with no accounts to create. For linear equations practice at the board, write x = 4 and ask pupils to build equations with that answer, such as 3x + 2 = 14 or x + 9 = 13. Classmates then swap and solve them. To see who is getting quicker at finding x, add the schools plan, priced per student, with its teacher dashboard.

Math practice · reimagined

Algebra Equations Game

This algebra game for solving equations runs from x + 3 = 11 to x² − 10x + 25 = 0, and no answer ever needs a fraction or a decimal. Your rival hunts the same x, so pin it down first and your fighter strikes.

Ages 4–99+ · no download · plays in your browser · 23 languages

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What is an equation in algebra?

An equation in algebra is a statement that two amounts are equal, where a letter such as x stands for a number nobody has told you yet. Solving it means finding the value that makes the statement true. Picture a closed box of marbles and 3 loose ones, 12 marbles in all. The box holds 9.

Every level of Equations

Example: solve 6x + 4 = 28

Read 6x as six times x, so six copies of the unknown number, plus 4, make 28.
Take 4 away from both sides: 28 minus 4 leaves 24, so 6x = 24.
Ask which number times 6 gives 24. Since 6 × 4 = 24, x must be 4.
Check it: 6 × 4 + 4 = 28, so you type 4.

Learn it step by step

An equation is a balance scale: whatever's on the left weighs the same as the right. The x is a mystery number, and your job is to get it alone.

For x + 4 = 11, undo the +4 by subtracting 4 from BOTH sides → x = 7. Whatever you do to one side, do to the other so the scale stays level.

Type the value of x.

Tips and common mistakes

Say 5x aloud as “five times x”. Hearing the hidden times reminds you to free x by dividing by 5, not by taking 5 away.
A common mistake with x² = 36 is halving 36 to get 18. The small 2 means x times x, so ask which number times itself makes 36: 6.
Play “think of a number” at dinner: double a secret number, add 5 and announce 17. Your child writes 2x + 5 = 17 and works back to 6.

How to play

Each round shows one equation, such as 3x + 8 = 14, and you type the value of x on the keypad, here 2. Higher levels add squares, and some answers need the minus key: x² + 8x + 16 = 0 is solved by −4. Get there before your rival and Broccoli attacks, and a fast answer hits hardest.

— Quick answers —

Equations: the short FAQ

What does solve for x mean?: To solve for x means to find the number that x stands for, the one that makes both sides of the equation equal. In x + 6 = 7, x is 1, because 1 + 6 = 7 and no other number works. You reach it by undoing what was done to x, step by step, until one side reads just x.
How do you solve equations with x on both sides?: Gather the x terms on one side and the plain numbers on the other, then solve what is left. Take 9x + 4 = 3x + 34. Subtracting 3x from both sides gives 6x + 4 = 34, and subtracting 4 gives 6x = 30. Since 6 × 5 = 30, x = 5. Put 5 back in, and both sides come to 49.
How do you remember which step undoes which?: Think of the operations as partners: adding and subtracting undo each other, multiplying and dividing undo each other, and a square root undoes squaring. Undo the last thing done to x first. In 4x + 7 = 31, the 7 was added last, so take it away first to get 4x = 24. Then divide by 4, and x = 6.
Why does my child find letters in equations confusing?: Letters feel strange at first because, until algebra, every symbol in a calculation stood for a number you could see. Call x a secret number instead, and start with equations your child can guess, such as x + 5 = 12. Once guessing gets slow on bigger equations, the undoing steps start to feel like a shortcut rather than a rule.
What does this algebra equation game cost a school, and how does it fit a lesson?: Nothing: every equation level is free for a class and opens in a browser on school laptops or tablets, with no accounts to create. For linear equations practice at the board, write x = 4 and ask pupils to build equations with that answer, such as 3x + 2 = 14 or x + 9 = 13. Classmates then swap and solve them. To see who is getting quicker at finding x, add the schools plan, priced per student, with its teacher dashboard.

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