Problem Solving (PS) | Re: If (3 + a)(a/10 - 0.4) = -1, then a could be

We can simplify the given equation:

(3 + a)(a/10 - 4/10) = -1

(3 + a)[(a-4)/10] = -1

(3 + a)(a - 4) = -10

a^2 - a - 12 = -10

a^2 - a - 2 = 0

(a - 2)(a + 1) = 0

a = 2 or a = -1

Answer: D

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