Answers in order from top to bottom:
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Step-by-step explanation:
To get each answer shown above, we replace each x value with a single specific value.
In the top row, we have x = 1. So we'll replace every x with 1 to get...
f(x) = 2x-1
f(1) = 2(1)-1
f(1) = 2-1
f(1) = 1
So that's why 1 goes in the first box.
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We repeat the same structure of steps for x = 0
f(x) = 2x-1
f(0) = 2(0)-1
f(0) = 0-1
f(0) = -1
Meaning that -1 goes in the second box.
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Repeat for x = -1
f(x) = 2x-1
f(-1) = 2(-1)-1
f(-1) = -2-1
f(-1) = -3
When we subtract a positive from a negative, we're really adding the two positive versions of the number, and then making the final result negative.
So -3 goes in the third box.
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Repeat for x = 2
f(x) = 2x-1
f(2) = 2(2)-1
f(2) = 4-1
f(2) = 3
We have 3 go in the fourth box.
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Side note: This is a linear function in slope intercept form y = mx+b. We have m = 2 as the slope and b = -1 as the y intercept.