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Question:for a negative monomial times a trinomial with different signs on the terms [for example: -3x(2xy + 3y 2x)] and show each step of the distribution. Why do you think many students make sign errors on this type of problem? What would be your advice to a student who has trouble with the signs?

Answers:-3x(2xy + 3y - 2x) (-3x)(2xy) + (-3x)(3y) + (-3x)(-2x) -6x^2y - 9xy + 6x^2 After you distribute the terms, try leaving the signs blank. Look back at the terms you've multiplied and/or divided and if you have an even number (2, 4, 6,..) of negatives, your answer will be positive. If you have an odd number (1, 3, 5,..) of negatives, your answer will be negative.

Question:Give an example of using the distributive property for a negative monomial times a trinomial with different signs on the terms [for example: -3x(2xy + 3y 2x)] and show each step of the distribution. Why do you think many students make sign errors on this type of problem? What would be your advice to a student who has trouble with the signs?

Answers:-2x(4xy+3y-1) -2x(4xy) =-8 x squared y -2x(3y)= -6xy -2x(-1)= 2x -8x squared y minus 6xy plus 2x is the answer. Students make errors because they don't have a good method of doing it. They try to start negative and count toward zero. All you have to do is master the signs. My advice is if you have 2 negatives the answer is positive. One negative and one positve is always negative positive and positive is always positive (in multiplication)

Question:signs of the terms .[for example: -3x(2xy + 3y 2x)] and show each step of the distribution. Why do you think many students make sign errors on this type of problem? What would be your advice to a student who has trouble with the signs?

Answers:-3x(2xy + 3y 2x) ___________________ -3x times 2xy = -6x^2y -3x time 3y = -9xy -3x time -2x = 6x^2 Answer: -6x^2y-9xy+6x^2 positive times positive = positive negative times negative = positive positive times negative = negative

Question:Give an example of using the distributive property for a negative monomial times a trinomial with different signs on the terms [for example: -3x(2xy + 3y 2x)] and show each step of the distribution.

Answers:I'll use your example: First Step : Distribute -3x to the three terms -3x(2xy) + -3x(3y) + -3x(-2x) = -6x ^2y + -9xy + 6x^2 Then, that is pretty much it since it is already simplified. There might be a certain order it has to be in, but i don't remember Sorry :( If you have trouble multiplying it still, look at it like this : (-3 * x * 2 * x * y) + (-3 * x * 3 * y) + (-3 * x *-2 * x) ALSO : -remember that a negative number multiplied by a negative number is a positive number -and a negative number multiplied by a positive number is a negative number Sorry that this is like a day later than posted, so it might be useless, but hope that helps :)