Which of the following coordinates exist on the line [tex]\( y = 3x + 1 \)[/tex]?

A. [tex]\((2,6)\)[/tex]

B. [tex]\((3,1)\)[/tex]

C. [tex]\((-1,-2)\)[/tex]

D. [tex]\((-3,4)\)[/tex]



Answer :

To determine which of the given coordinates exists on the line described by the equation [tex]\( y = 3x + 1 \)[/tex], we will test each point by substituting the [tex]\( x \)[/tex] and [tex]\( y \)[/tex] values into the equation and checking if the equality holds true.

Let's test each coordinate one by one:

A. [tex]\((2, 6)\)[/tex]

1. Substitute [tex]\( x = 2 \)[/tex] into the equation [tex]\( y = 3x + 1 \)[/tex]:
[tex]\[ y = 3(2) + 1 = 6 + 1 = 7 \][/tex]
2. Compare the computed [tex]\( y \)[/tex] value (which is 7) with the given [tex]\( y \)[/tex] value (which is 6).
[tex]\[ 7 \neq 6 \][/tex]
So, [tex]\((2, 6)\)[/tex] does not lie on the line [tex]\( y = 3x + 1 \)[/tex].

B. [tex]\((3, 1)\)[/tex]

1. Substitute [tex]\( x = 3 \)[/tex] into the equation [tex]\( y = 3x + 1 \)[/tex]:
[tex]\[ y = 3(3) + 1 = 9 + 1 = 10 \][/tex]
2. Compare the computed [tex]\( y \)[/tex] value (which is 10) with the given [tex]\( y \)[/tex] value (which is 1).
[tex]\[ 10 \neq 1 \][/tex]
So, [tex]\((3, 1)\)[/tex] does not lie on the line [tex]\( y = 3x + 1 \)[/tex].

C. [tex]\((-1, -2)\)[/tex]

1. Substitute [tex]\( x = -1 \)[/tex] into the equation [tex]\( y = 3x + 1 \)[/tex]:
[tex]\[ y = 3(-1) + 1 = -3 + 1 = -2 \][/tex]
2. Compare the computed [tex]\( y \)[/tex] value (which is -2) with the given [tex]\( y \)[/tex] value (which is also -2).
[tex]\[ -2 = -2 \][/tex]
So, [tex]\((-1, -2)\)[/tex] does indeed lie on the line [tex]\( y = 3x + 1 \)[/tex].

D. [tex]\((-3, 4)\)[/tex]

1. Substitute [tex]\( x = -3 \)[/tex] into the equation [tex]\( y = 3x + 1 \)[/tex]:
[tex]\[ y = 3(-3) + 1 = -9 + 1 = -8 \][/tex]
2. Compare the computed [tex]\( y \)[/tex] value (which is -8) with the given [tex]\( y \)[/tex] value (which is 4).
[tex]\[ -8 \neq 4 \][/tex]
So, [tex]\((-3, 4)\)[/tex] does not lie on the line [tex]\( y = 3x + 1 \)[/tex].

Based on the calculations above, the coordinate that lies on the line [tex]\( y = 3x + 1 \)[/tex] is:
C. [tex]\((-1, -2)\)[/tex].