Answer: 27
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Work Shown:
a = -3
a^2 = (-3)^2 .... squaring both sides
a^2 = 9
3a^2 = 3*9 .... multiply both sides by 3
3a^2 = 27
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Or you could do it this way
3a^2 = 3(-3)^2 ... replace 'a' with -3
3a^2 = 3(9)
3a^2 = 27