Let the letter d be the unknown number, when we double it we get the algebraic expression 2d.Įxample 7: Write an algebraic expression for the math phrase ” the quotient of a number and 7″. In this case, we want to double an unknown value or quantity. Solution: The word “twice” means we are going to double something. It means 5 times the unknown number m.Įxample 6: Write an algebraic expression for the math phrase ” twice a number”. Selecting the letter m as our variable, the algebraic expression for this math phrase is simply 5 m. Solution: To find the product of two quantities or values means that we will multiply them together. If we choose our variable to be the letter a, we get 8 - a.Įxample 5: Write an algebraic expression for the math phrase ” the product of 5 and a number”. In other words, we are going to subtract the unknown number from the number 8. While the quantity that comes after it becomes the minuend. The first quantity that comes before the “less than” keywords which is ” a number” is the subtrahend. Solution: Be very careful when dealing with the keywords “less than”. If we decide to use the letter x as our variable, the answer becomes 1 − x.Įxample 4: Write an algebraic expression for the math phrase ” a number less than 8″. That means the number 1 is the minuend and the unknown number is the subtrahend. The number 1 comes first then an unknown number comes in second. In addition, when you encounter this math word (difference) make sure to pay attention to the order. Solution: The word “difference” suggests that we are going to subtract. Either of the two is a correct answer.Įxample 3: Write an algebraic expression for the math phrase ” the difference of 1 and a number”. Since addition is commutative, we can rewrite it as k 10. Using the letter k as the variable, we can translate the statement above as 10 k. This means that an unknown number has been added to 10. Solution: The keywords “increased by” imply addition. It is also okay to write your answer as 4 y because addition is commutative – that is, switching the order of addition doesn’t change the sum.Įxample 2: Write an algebraic expression for the math phrase ” 10 increased by a number”. When we add the variable y and 4, we have y 4. In this case, let’s agree to use y for the variable. Since we don’t know the value of the number, we can use a variable to represent it. Notice that we want to add two quantities: one unknown number and the number 4. Solution: The word “sum” immediately gives us the hint that we are going to add here.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |