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He weights of 2-pound bags of best dog food are approximately normally distributed with a given mean  and standard deviation  according to the empirical rule, what percentage of the bags will have weights within 3 standard deviations of the mean? 47.5%68%95%99.7%

Bring the fraction a/a-4 to a denominator of 16-a^2

What is the area of a triangle with vertices at (-3 3) (-3,2) and (1,2)?