Addition
As we make questions about math equations, let’s review the basic grammar rules for forming questions.
The verbs in a sentence are responsible for what form the question takes.
In a mathematical equation, the equal sign (=) is the verb.
The To Be Verb
For the equal sign, we will begin with an easy way to say it.
- is
Look at this simple equation:
2 + 3 = 5 “two and three is five”
On the right side of the equal sign, there is just one number (five). This side of the equal sign is singular with just one number, right?
On the left side of the equal sign, there are two numbers (two and three). That makes it plural, right? Not in math.
In the language of math, the operation, in this example addition, is a singular phrase. In math, 2 + 3 is a single idea. Teachers and students of English grammar can think of the chunk of language of 2 + 3 as the subject of the sentence. In math, this subject is always singular.
Since the subject is singular, the verb must be in singular form, too. The “to be” form “is” refers to 3rd-person singular grammar. This is the grammar of basic equations in math. This is why we use “is” for the equal sign no matter how many numbers or operations are on a side.
Now we can understand how to make a question to check the answer.
How does English form a question with a “to be” verb when that verb is “is”?
Let’s begin with the Yes/No questions.
2 + 3 = 5 “two and three is five”
“Two and three” is the subject. “Is” is the verb. They change places.
Is two and three five?
The answer can only be yes or no. This is called a Yes/No question.
Your Turn — Practice yes/no questions with “is” for the equal sign
The equal sign has a lot of phrases with “is“. Let’s review two of them.
- is equal to
- is equivalent to
10 times 10 = 100
The equation is, “Ten times ten is equal to a hundred.”
The question is, “Is 10 times 10 equal to 100?”
20 multiplied by 20 = 400
The equation is, “Twenty multiplied by twenty is equivalent to four hundred.”
The question is, “Is 20 multiplied by 20 equivalent to 400?”
Your Turn — Practice yes/no questions with “is equal to” and “is equivalent to” for the equal sign
Let’s continue to review the other “is” phrases that use the word “same” in them.
- is the same as
- is the same amount as
- is the same value as
30 + 30 = 60
The equation is, “Thirty added to thirty is the same as sixty.”
The question is, “Is 30 added to 30 the same as 60?”
40 + 40 = 80
The equation is, “Forty add forty is the same amount as eighty.”
The question is, “Is 40 add 40 the same amount as 80?”
50 + 50 = 100
The equation is, “Fifty plus fifty is the same value as a hundred.”
The question is, “Is 50 plus 50 the same value as 100?”
Your Turn — Practice yes/no questions with “is” “same” phrases
The Other (non-To Be) Verbs
The equal sign works as the verb in mathematical sentences. Do you remember the ways to say the equal sign without using the “to be” verb “is”?
4 + 7 = 11 can be said as, “four plus seven equals eleven” or “four and seven makes eleven”
Notice the final -s at the end of both of the words “equal” and “make” used for the equal sign. The final -s identifies the verb as a 3rd-person singular verb as we saw with the word “is”. Let’s learn about the “equals” verb first.
“equals”
How can we make a yes/no question without the “to be” verb “is”?
Let’s look at the equation.
4 + 7 = 11 “four plus seven equals eleven”
We must use the 3rd-person singular verb grammar rule to make a yes/no question. We begin the sentence with “does” and drop the final -s.
For example,
4 + 7 = 11 The question is, “does four plus seven equal eleven”?
17 + 14 = 31 The question is, “does 17 and 14 equal 31?
Your Turn — Practice yes/no questions for “equals”
“makes”
The word makes for the equal sign also uses the final -s for the 3rd person singular verb form. The way to make a yes/no question for “makes” is the same as above for “equals”.
For example,
5 + 3 = 8 The question is, “does five plus three make eight”?
23 + 19 = 42 The question is, “does 23 and 19 equal 42?
Your Turn — Practice yes/no questions for “makes”
Summary
- The equal sign is the verb in mathematical equations
- If the equation sign is used with “is”, the question formation follows the “to be” grammar pattern.
- If the equation sign is said with a non-to be verb, the question formation follows the grammar pattern that uses “does”.
- Yes/No questions are used to confirm if an answer is correct.
