Question

A line passes through the points (5, 17) and (12, 38). A second line passes through the points (5, 26) and (8, 44). At what point do the two lines intersect?


(3, 11)


(4, 14)


(0, 0)


(2, 8)



Answers

Answered by GPT-4o mini
Let's find the equations of the two lines first.

**Line 1** passes through the points (5, 17) and (12, 38).

To find its slope \( m \):
\[
m = \frac{y_2 - y_1}{x_2 - x_1} = \frac{38 - 17}{12 - 5} = \frac{21}{7} = 3
\]

Now, we use the point-slope form of the equation of a line, which is \( y - y_1 = m(x - x_1) \).
Using the point (5, 17):
\[
y - 17 = 3(x - 5)
\]
\[
y - 17 = 3x - 15
\]
\[
y = 3x + 2
\]

So, the equation of Line 1 is:
\[
y = 3x + 2
\]

**Line 2** passes through the points (5, 26) and (8, 44).

To find its slope \( m \):
\[
m = \frac{y_2 - y_1}{x_2 - x_1} = \frac{44 - 26}{8 - 5} = \frac{18}{3} = 6
\]

Using the point-slope form of the equation of a line with the point (5, 26):
\[
y - 26 = 6(x - 5)
\]
\[
y - 26 = 6x - 30
\]
\[
y = 6x - 4
\]

So, the equation of Line 2 is:
\[
y = 6x - 4
\]

To find the intersection of the two lines, we need to set their equations equal to each other:
\[
3x + 2 = 6x - 4
\]

Now, rearranging the equation:
\[
2 + 4 = 6x - 3x
\]
\[
6 = 3x
\]
\[
x = 2
\]

Now, we substitute \( x = 2 \) back into either equation to find the corresponding \( y \).

Using Line 1's equation:
\[
y = 3(2) + 2 = 6 + 2 = 8
\]

Thus, the point of intersection is \( (2, 8) \).

Therefore, the two lines intersect at:
\[
\boxed{(2, 8)}
\]

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