Question

Difficulty: MediumCoordinate Geometry: Lines, Slopes, and Distance

In the xyxy-plane, line kk has a slope of 34\frac{3}{4} and passes through the point (2,1)(2, 1). Line kk intersects the line x=10x = 10 at point PP. What is the distance between point PP and the point (2,1)(2, 1)?

Answer: 10

Answer

10
Point P lies on the line x = 10, so its x-coordinate is 10. The horizontal change from x = 2 to x = 10 is 8 units. Given that line k has slope 3/4, the corresponding vertical change is (3/4)(8) = 6 units. Therefore, point P has coordinates (10, 7). The distance between (2, 1) and (10, 7) is sqrt((10 - 2)^2 + (7 - 1)^2) = sqrt(64 + 36) = sqrt(100) = 10.

Step-by-Step Solution

1
Determine the coordinates of point P
P is located at (10, 7)
Since P lies on the line x = 10, its x-coordinate is 10. The horizontal distance from (2, 1) to P is 10 - 2 = 8. Using the slope m = 3/4, the vertical change is (3/4) * 8 = 6, so the y-coordinate of P is 1 + 6 = 7.
2
Calculate the distance between (2, 1) and (10, 7)
The distance is 10
Using the distance formula sqrt((10 - 2)^2 + (7 - 1)^2) = sqrt(8^2 + 6^2) = sqrt(64 + 36) = sqrt(100) = 10.

Key Concept

Slope definition and distance formula in coordinate geometry
Estimated Time:1m 30s
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