evaluate (2x/5+3y/4-4z/7)to the power of 2this is from chapter Expansions(including substitution)  

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nathanshields | High School Teacher | (Level 1) Associate Educator

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Evaluate is not the right word here, since that means to find the value.  I believe you mean "expand" since the chapter is called expansions and I don't see anything else to do with this problem.

Remember, squaring means multiplying by itself.  So you're interested in` `

` ``((2x)/5+(3y)/4-(4z)/7)``((2x)/5+(3y)/4-(4z)/7)`

Now you just use the distributive property 3 times to multiply these trinomials:


` ``+(3y)/4*(2x)/5+(3y)/4*(3y)/4-(3y)/4*(4z)/7`` `

` ``-(4z)/7*(2x)/5-(4z)/7*(3y)/4+(4z)/7*(4z)/7`` `

It's a bit tedious, but now you combine all the like terms. I'll start by multiplying each pair of fractions:




Now combine the like terms


And you're done!

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