Answer:
f(x) = x +3
Explanation:
The first differences for adjacent x-values are all 1, so this is a linear function. Because those differences are all 1, it is a linear function with a slope of 1. We observe that f(0) = 3, so that is the y-intercept.
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The slope-intercept form of a linear function is ...
y = mx + b . . . . . where m is the slope (1) and b is the y-intercept (3).
A suitable function rule is ...
f(x) = x +3