Steps for Easy Double-Digit Subtraction

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What is the very first step when you see a subtraction problem like $56 - 23$?

Line up the numbers vertically so the ones are above the ones and the tens are above the tens.

When subtracting two-digit numbers, which column do you always start with?

Always start with the ones column, which is on the far right.

After you subtract the ones, what is the second and final step?

Subtract the numbers in the tens column, which is on the left.

In the problem $48 - 15$, what is the subtraction you do in the ones column?

$$8 - 5$$

In the problem $48 - 15$, what is the subtraction you do in the tens column?

$$4 - 1$$

What does 'without regrouping' or 'no borrowing' mean in subtraction?

It means the top digit in each column is bigger than or equal to the bottom digit, so you don't have to borrow from the next column.

True or False: It's okay to subtract the tens column before the ones column.

False. You must always start with the ones column.

Let's set up the problem $79 - 34$ to be solved. How should it look?

The number $79$ should be on top of $34$, with the $9$ directly over the $4$ and the $7$ directly over the $3$.

Why is it important to line up the numbers by place value?

So you subtract ones from ones and tens from tens. If they are not lined up, you will get the wrong answer.

After subtracting the ones and then the tens, what do you have?

You have the final answer to the subtraction problem!