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Question
The algebraic equation "8x-7x+5x-19y" is simplified to "-26y+13x", correct?

- Whether or not this answer is right or wrong, can you show me the steps to solve? Thanks

In this problem, note that you have two unknown variables x and y. You want to collect their coefficients together to simplify the expression. This is a matter of adding together the coeffcients of x together, including whether they are positive or negative, and then do the same for y. The expression can be written (using the associative law)

(8-7+5)x + (-19)y = 6x - 19y.

It looks like you grouped the terms (cofficients) with the "+" signs together and the ones with the "-" together and then assigned the resulting sums to either x or y, sort of arbitrarily, which isn't correct. Plus and minus signs can be combined together as needed but they always have to be associated with the variable they are multiplying.

Randy

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#### randy patton

##### Expertise

college mathematics, applied math, advanced calculus, complex analysis, linear and abstract algebra, probability theory, signal processing, undergraduate physics, physical oceanography

##### Experience

26 years as a professional scientist conducting academic quality research on mostly classified projects involving math/physics modeling and simulation, data analysis and signal processing, instrument development; often ocean related

Publications
J. Physical Oceanography, 1984 "A Numerical Model for Low-Frequency Equatorial Dynamics", with M. Cane

Education/Credentials
M.S. MIT Physical Oceanography, B.S. UC Berkeley Applied Math

Past/Present Clients
Also an Expert in Oceanography