4

Set 10: Exponential Functions (Advanced)

Explanation

Answer: A

The graph of y=a(b)xy = a(b)^x passes through (0,50)(0, 50) and (2,200)(2, 200). What is the value of bb?

A.

2

✓ Correct
B.

4

C.

50

D.

100

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Use both points to find bb. 1. Find aa: At (0,50)(0, 50), a(b)0=a=50a(b)^0 = a = 50. 2. Find bb: At (2,200)(2, 200), 50(b)2=20050(b)^2 = 200. 3. Solve: b2=4b^2 = 4, so b=2b = 2 (positive). Strategic Tip: Once you know aa, substitute the second point to solve for bb. Choice B is incorrect because this is b2b^2, not bb. Choice C is incorrect because this is the initial value aa. Choice D is incorrect because this is the yy-value at x=2x=2.

Key Steps:

The correct answer is 2

Why others are wrong:
B: Choice B is incorrect and may result from a calculation error.
C: Choice C is incorrect and may result from a calculation error.
D: Choice D is incorrect and may result from a calculation error.

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