Advanced Math practice question

Answer: A. x + 11

Common denominator (x − 1)(x + 2): numerator = 4(x + 2) − 3(x − 1) = 4x + 8 − 3x + 3 = x + 11.

Why the other answers are wrong

B. x + 5

x + 5 comes from 4x + 8 − 3x − 3, forgetting to distribute the minus sign to −1.

C. 7x + 5

7x + 5 adds the two numerators instead of subtracting.

D. x − 5

x − 5 comes from 4(x − 1) − 3(x + 2), cross-multiplying by the wrong factors.

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