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Marco is turning the expression (x-4)^2 into a trinomial. He writes down what is shown below. What is his error?

Marco is turning the expression (x-4)^2 into a trinomial. He writes down what is shown-example-1
User Shameek
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2 Answers

3 votes

Answer:

Explanation:

first, let's solve the equation ourselves.

(x-4)^2= (x-4)(x-4)= x^2−8x+16

now, we can see what's different about the two.

we can say that Marco's answer had the number 16 as a negative, when it was supposed to be positive. Marco wrote the incorrect sign.

User Yuan
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(x-4)(x-4)
=x^2-4x-4x+16
=x^2-8x+16
it’s +16, not negative. he forgot that when you add two negatives together, it becomes positive.
User Rwking
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