Remove the parentheses and simplify 3a^2-6ab+3b^2-5(-6a^2+7ab-7b^2)

Select the correct answer. what is the exact value of sin (157.5°)? a. 'sqrt(2 - sqrt(2))/2 b. *"-"'sqrt(2 + sqrt(2))/29 c.'sqrt(2 + sqrt(2))/4" d. "-"sqrt(2 + sqrt(2))/4)

Xy x xy if a and b are positive integers such that a*b=9 and b*a=72 what is the value of a/b

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