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How do you find the sum or difference of #(2x+3x^2)-(7-8x^2)#?

Answer 1

#11x^2+2x-7#

#(2x+3x^2)-(7-8x^2)#

#(2x+3x^2)+[-1\cdot(7-8x^2)]# #(2x+3x^2)+[-1(7)+(-1)(-8x^2)]# apply distributive property to second half #(2x+3x^2)+[-7+8x^2]# simplify #2x+3x^2-7+8x^2# remove parentheses and change signs where needed #2x+11x^2-7# add like terms #11x^2+2x-7# reorder to quadratic format

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Answer 2

Eva Abramson

To find the sum or difference of (2x+3x^2)-(7-8x^2), distribute the negative sign inside the parentheses of the second expression and then combine like terms:

(2x + 3x^2) - (7 - 8x^2) = 2x + 3x^2 - 7 + 8x^2 = (3x^2 + 8x^2) + 2x - 7 = 11x^2 + 2x - 7

Therefore, the sum or difference of the expressions is 11x^2 + 2x - 7.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.