A respeito dos produtos notáveis, assinale a alternativa que apresenta corretamente um deles: (x + a)² = x² + a²
(x + a).(x - a) = x² + xa + a²
(x – a)² = x² – a²
(x – a)² = x² – 2x – a²
(x – a)² = x² – 2xa + a²

50 min

step-by-step explanation:

they will be decreasing both their times in half

60 / 2 = 30

40/2 = 20

30 + 20 = 50

the mistake in the pattern is that :

b. the decimal point was moved one too many place values each time

the correct pattern could be made by :

b. moving the decimal point to the right the same numbers of place values as the exponents

4.

step-by-step explanation:

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