Question

I. 81x - 117√x + 40 = 0

II. 81y - 225√y + 136 = 0

A if x Correct Answer Incorrect Answer
B if x>y Correct Answer Incorrect Answer
C if x≤y Correct Answer Incorrect Answer
D if x=y or the relationship cannot be established. Correct Answer Incorrect Answer
E if x≥y Correct Answer Incorrect Answer

Solution

I. 81x - 117√x + 40 = 0 81x - 72√x - 45√x + 40 = 0 9√x (9√x - 8) -5 (9√x - 8)= 0 (9√x -5) (9√x -8) = 0 x = 25/81, 64/81 II. 81y - 225√y + 136 = 0 81y - 72√y - 153√y + 136 = 0 9√y (9√y -8) - 17 (9√y - 8) = 0 (9√y - 8) (9√y-17) = 0 y = 289/81, 64/81 Hence, x ≤ y

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