Answer: y = 7x
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Step-by-step explanation:
Pick two points from the table such as (1,7) and (2,14)
Apply the slope formula.

This means y = mx+b updates to y = 7x+b
Plug a point like (1,7) into that equation to solve for b.
y = 7x+b
7 = 7*1+b
7 = 7+b
7-7 = b
0 = b
b = 0
We go from y = 7x+b to y = 7x+0
That simplifies to the final answer of y = 7x
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Check:
Plug x = 2 to get
y = 7x
y = 7*2
y = 14
This shows (2,14) is on the line, and it matches with the table.
I'll let you check the other x values.
Another way to verify is to use a graphing app like GeoGebra or Desmos.