5

Set 10: Exponential Functions (Intermediate)

Explanation

Answer: A

Identify the equation for the graph passing through (0,2)(0, 2) and (1,10)(1, 10).

Exponential Function

A.

y=2(5)xy = 2(5)^x

✓ Correct
B.

y=5(2)xy = 5(2)^x

C.

y=2(10)xy = 2(10)^x

D.

y=2+8xy = 2 + 8x

Detailed Explanation

Choice A is correct. Choice A is the correct answer. Find aa and bb. 1. Find a: Y-intercept is 2, so a=2a=2. 2. Find b: yy goes from 2 to 10. 2×b=10    b=52\times b = 10 \implies b=5. 3. Equation: y=2(5)xy = 2(5)^x. Strategic Tip: b=y2/y1b = y_2 / y_1 when Δx=1\Delta x = 1. Choice B is incorrect because it swaps aa and bb. Choice D is incorrect because it is linear.

Key Steps:

The correct answer is y=2(5)xy = 2(5)^x

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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