Which expression is equivalent to the given expression? 3x^2+5x-7(x^2+4)

3x + 4y = 5 x- 3y = -7 solve by substitution

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Assume that adults have iq scores that are normally distributed with a mean of mu equals 100 and a standard deviation sigma equals 20. find the probability that a randomly selected adult has an iq between 80 and 120.assume that adults have iq scores that are normally distributed with a mean of mu equals 100 and a standard deviation sigma equals 20. find the probability that a randomly selected adult has an iq between 80 and 120.