How do you solve for factoring polynomials with leading coefficient > 1

The contents of 3838 cans of coke have a mean of x¯¯¯=12.15x¯=12.15. assume the contents of cans of coke have a normal distribution with standard deviation of σ=0.12.σ=0.12. find the value of the test statistic zz for the claim that the population mean is μ=12.μ=12.

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Find the zeros of each function. f(x) = 6x^2 - 7x - 20