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## Algebra 1 (Eureka Math/EngageNY)

### Unit 1: Lesson 5

Topic B: Lesson 9: Multiplying monomials

# Multiplying monomials to find area

Learn to express the area of a rectangle with length 4y and width 2y as a monomial. Created by Sal Khan and Monterey Institute for Technology and Education.

## Want to join the conversation?

• What's monomial?
• what is the definition of a monomial
• A monomial is a number, a variable, or the product of a number and one or more variables with nonnegative integer exponents. it has only one term.
• Simplify (11k) to the second power
• (11k)^2 is made more simple is you write is as 11*11* then add the k*k which will simplify to 121K to the power of 2 also written as 121k^2. I hope this helps.
• I kind of don't understand why it would be y squared, because 1x1 is 1, so why is yxy y squared?
• Any number times itself = that number squared (or to the power of 2.
It just happens that 1^2 = 1 * 1 = 1
For most any other number, that relationship does not exist. For example: 3^2 = 3*3 = 9
Since we don't know the actual value of "y", we can't calculate "y * y". So, we write it in exponent form: "y^2".
Hope this helps.
• where are the practice problems for this section?
• There is not any, sorry. if you want to request that feature go to "Guidelines" > "request for features" at the bottom of the guidelines page
(1 vote)
• Wait, so is 8 y^2 a polynomial or a monomial?
• Monomial. A monomial is an expression that is the product of constants and nonnegative integer powers of x, such as 5x^7. The coefficient--the number 5--is the constant term which is multiplying the variable term x. In your example, 8 is the coefficient and y is the variable term. Keep in mind, to be a monomial, the variable term needs to be raised to a positive power; if the exponent is negative or fractional, then the expression is not a monomial.
(1 vote)
• So can you solve for the y? Or is it just left at the equation?
• I believe that it is just left at the equation. You can't solve the equation unless you're given a value for y. For example, if the problem in the video said that y = 3, then we can substitute y for 3 and then solve, but we can't solve for y. Thanks for asking that. Hope this helps.
(1 vote)
• pls help me:
What is a monomial? i still don't get it...HELP!
(1 vote)
• It is a polynomial with only 1 term. Example: 3x^2, 2x, 3.56794735y. Anything with only 1 term.