Released STAAR Algebra I EOC · 2025 · Item 18 · 1 point

Walkthrough: Algebra I 2025, Item 18

A.9C · Exponential Functions · unscored study

The table represents some points on the graph of an exponential function. Which function represents the relation shown in the table?

$x$	$P(x)$
−1	270
0	90
1	30
2	10

$P(x) = 30\left(\frac{1}{3}\right)^x$
$P(x) = 90(3)^x$
$P(x) = 90\left(\frac{1}{3}\right)^x$
$P(x) = 30(3)^x$

1. Understand the question

In $P(x) = ab^x$ , $a$ is the value at $x = 0$ and $b$ is the constant ratio between consecutive values.

Try the question on your own first, then reveal one step at a time.

2. Solve it step by step

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