The answer is: [C]: " y = 3x + 1 " .
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Note: By looking at the graph, we see that it passed through the point, " (0, 1) " (at the y-intercept).
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Consider choice: [A]: "y = 3x" ; When "x = 0" ; what does "y" equal ?
→ y = 3x = 3(0) = 0 ; → "(0, 0)" is a solution; NOT "(0, 1)" ; so rule out "[A]" .
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Consider choice: [B]: "y = 3x − 1" ; When "x = 0" ; what does "y" equal ?
→ y = 3(0)−1 =0−1 = -1; → "(0, -1)" is a solution; NOT "(0, 1)" ; so rule out "[B]" .
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Consider choice: [C]: "y = 3x + 1" ; When "x = 0" ; what does "y" equal ?
→ y = 3(0)+1 = 0+1 = 1; → "(0, -1)" is a solution; so "choice [C]" is possible.
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Consider choice: [D]: "y = 3x² + 1"; When "x = 0" ; what does "y" equal ?
→ y = 3(0²)+1 = 0+1 = 1; → "(0, 1)" is a solution; so "choice [D]" is possible.
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However; choice: [D]: is a parabola, not a line; so we determine that the correct answer is: Choice [C]: "y = 3x + 1" .
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