Question

-2√7 + 3√5 + 4√7 + 4√5 =?

Answer 1

-2√7 + 3√5 + 4√7 + 4√5  agrupando termes semelhantes
=-2√7+4√7+3√5+4√5  isolando o termo comum
=(-2+4)√7+(3+4)√5
=2√7+7√5

para o caso 
9√8 - 2√13 - 5√13 - 6√8
=9√2x2²-2√13-5√13-6√2x2²
=9x2√2-2√13-5√13-6x2√2
=18√2-2√13-5√13-12√2
=(18-12)√2-(2+5)√13
=6√2-7√13

Answer 2

-2/7 + 4/7 + 4/5 + 3/5
2/7 + 7/5


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