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Course: Algebra 1 (Eureka Math/EngageNY)>Unit 4

Lesson 1: Topic A: Lessons 1-2: Factoring monomials

Worked example: finding the missing monomial factor

Follow along as Sal works an example to show you how to factor monomials by isolating variables in equations. Learn how to use exponent properties to rewrite complex expressions and get a firm grasp on the crucial role that coefficients and exponents play in this process. This knowledge will empower you to solve for unknown factors in any monomial equation.

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• what does this all mean? What are non-fractional co-efficients?
• Non-fractional co-efficients? A coefficient is a numerical or constant quantity placed before and multiplying the variable in an algebraic expression (e.g., 4 in 4x^y). Non fractional means it's not a fraction.
• But isn’t dividing by a variable a big no no?

At , why would it be different if the coefficient or exponent were fractional?
• What grade level is this considered?
• This video was under the Algebra 2 course, polynomial factorization, then factoring monomials. I'm taking it in Middle school. So I hope this helped
• I recently came across a question about how to solve 16x^2-32x+15 . Would it make more sense to use quadratic formula or to think about it like what multiplies to 16*15 and what adds to -32? And why you think that this is easier?
• I would use factoring. The factors you need are: -12 and -20.
The polynomial has some large numbers. If you use the quadratic formula you can get even larger numbers, particularly inside the radical. Then, you are faced with simplifying the radical.
• What are the instances when dividing by the variable is okay and what are the instances when doing so would not be okay because it would be equivalent to cancelling out possible results?
(1 vote)
• When your variable can equal zero, you can't divide by it (as division by zero isn't defined). Here too, division removes a solution of x (x=0) but as finding x isn't our goal anyway, we can freely divide.
• I have a question why thus this algebra so important.
• At , Sal writing the -10x^3 under both, but shouldnt it be -10x^3 / -10x^3 AND (F) / -10x^3 ? Thanks
(1 vote)
• No because these two terms are being multiplied together rather than added. He did not have to use parentheses to separate them because they are all one term, but it is easier to see. If they were added instead of multiplied, then the opposite would be to subtract and that is a different problem.
• Do we need to specify that -10x^3 is not equal to 0 ?
(1 vote)
• why does sal make everything hard
(1 vote)
• How do you find the missing factor? and how do you find the factors of a Monomial?
(1 vote)
• 1)We do it the same way as we do it for natural numbers.
eg. Find another factor of 35
35- 5 and ?
Ans. 35/5 i.e.7

2) Let me explain with an example,
Factors of 8x^3 are-
>2x^2 and 4x
>x, 2x and 4x etc