Ready for Equations? What to Check First

Solving equations is where many students first find math hard. Usually the trouble is an earlier skill. Here is how to check those skills first.

By Thomas Lee · Updated

Why equations feel like a wall

For many students, the first page of equations is the moment math stops feeling like arithmetic. There is a letter in the problem, the answer is a number you have to find rather than calculate, and every step has to be written down. It is easy to conclude that the student "isn't an algebra person". Often, though, the difficulty is not the equation itself. Solving 5x+3=385x + 3 = 38 is a short chain of skills the student met years earlier, and if one link in that chain is weak, the whole problem feels hard.

That is good news, because those earlier skills are easier to fix than a vague feeling that algebra is difficult. Before starting equations, or when a student is stuck on them, it is worth checking each link separately.

A five-minute check

Give these six questions on a sheet of paper, without a calculator, and watch how they are answered as well as whether the answers are right. A correct answer that takes a long time to work out tells you as much as a wrong one.

  1. 56÷856 \div 8
  2. What number goes in the box? □+9=15\square + 9 = 15
  3. (−4)−(−9)(-4) - (-9)
  4. 3+4×53 + 4 \times 5
  5. Simplify 4x+2−x+54x + 2 - x + 5
  6. Expand 3(x+4)3(x + 4)

The answers are 7, 6, 5, 23, 3x+73x + 7 and 3x+123x + 12. Each question stands for one of the skills below.

1. Facts that come without thinking

Most equations end with a division. In 5x=355x = 35, the last step is 35÷5=735 \div 5 = 7, and a student who has to count up in fives to get there loses track of what the equation was about. On MathGem's easiest equation worksheets, every problem such as 6x=426x = 42 is a times-table fact read backwards; none goes beyond 9×99 \times 9. If the first question in the check was slow, a couple of weeks of daily times-table and division pages will do more for equations than any amount of equation practice.

2. Knowing that operations undo each other

The second question is an equation in disguise. A student who answers □+9=15\square + 9 = 15 by thinking "15 take away 9" already understands the main idea of solving equations: subtraction undoes addition, and division undoes multiplication. Younger children meet this as fact families (6+9=156 + 9 = 15, so 15−9=615 - 9 = 6). If the box question caused trouble, spend time on it before introducing xx. Writing xx instead of a box changes nothing about the thinking, and it helps when students see that.

3. Comfort with negative numbers

The equations on the first worksheets have positive whole-number answers, but negative numbers appear as soon as terms move from one side to the other: taking 3x3x away from both sides of 7x+4=3x+247x + 4 = 3x + 24 means thinking about −3x-3x. Later topics use negatives everywhere. A student who hesitates over (−4)−(−9)(-4) - (-9) will make sign mistakes that look like algebra mistakes. The integer worksheets practise one operation at a time, which makes it easy to find exactly which sign rule is the problem.

4. The order of operations, forwards and backwards

3+4×53 + 4 \times 5 is 23, not 35, because multiplication comes before addition. This matters for equations in a way that is easy to miss. To build 5x+35x + 3, you multiply by 5 and then add 3. To solve 5x+3=385x + 3 = 38, you undo those steps in reverse order: subtract 3 first, then divide by 5. Solving an equation is the order of operations run backwards, so a student who is unsure of the order going forwards will be guessing going backwards.

5. Reading and tidying expressions

The last two questions check whether the student can work with expressions before any equation appears. Simplifying 4x+2−x+54x + 2 - x + 5 needs two ideas: that 4x4x and −x-x can be combined but 4x4x and 2 cannot, and that the minus sign belongs to the xx after it. Expanding 3(x+4)3(x + 4) needs the 3 to multiply both terms inside the bracket; 3x+43x + 4 is a very common wrong answer. Harder equations, such as 3(x+4)=273(x + 4) = 27 or ones with xx on both sides, are mostly these two skills followed by a short solve. MathGem's Algebra level has separate worksheets for simplifying and for the distributive property, and they are worth doing before the harder equations.

6. The habit of checking

This one is not in the quiz because it is a habit rather than a skill. An equation is the rare kind of problem where students can always tell whether they are right: put the answer back in and see whether both sides match. For x=7x = 7 in 5x+3=385x + 3 = 38, 5×7+35 \times 7 + 3 is 38, so the answer is right. Students who build the habit on easy equations, where checking takes seconds, keep it when the equations get longer and checking really matters.

Starting equations

Once the check goes smoothly, the Solving Equations worksheets can start on Easy, with one-step equations such as x+7=12x + 7 = 12 and 6x=426x = 42, and move on to two steps and then brackets and variables on both sides. Every answer on those worksheets is a positive whole number, so a student can concentrate on the steps rather than the arithmetic.

If one of the six skills was shaky, it is usually better to pause equations for a week or two than to push on. A few pages of the earlier skill each day, alongside a single page of easy equations to keep the idea fresh, tends to work well. Students who come back to equations with fast facts and confident signs often find that the topic which felt like a wall is mostly a matter of writing one step per line.