Friday

July 25, 2014

July 25, 2014

Posted by **Lilly** on Monday, July 22, 2013 at 8:58pm.

Which is the distance between the point with the coordinates (1,2) and the line with the equation 2x-3y=-2?

- math -
**Steve**, Tuesday, July 23, 2013 at 4:44amdistance from (h,k) to ax+by+c=0 is

|ah+bk+c|/√(a^2+b^2)

so, you have

|1*2 - 2*3 + 2|/√(4+9) = 2/√13

or, if you can't recall the formula, you can work it out by realizing that the shortest distance will be along a perpendicular line through the point.

2x-3y = -2 has slope 2/3

The perpendicular thus has slope -3/2

Now you have a point and a slope, so the equation of the perpendicular line through (1,2) is

y-2 = -3/2 (x-1)

y = -3/2 x + 7/2

The perpendicular intersects at (17/13,20/13)

The distance from (1,2) to (17/13,20/13) is √(16/169+36/169) = √52/13 = 2/√13

**Related Questions**

Math - I have a series of questions that I did. They lead up to the last ...

math - Alright, let's say you want to get from one point to another, in a 3D box...

Math--Calculus - Let y = f(x) be the continuous function that satisfies the ...

math - Find an equation of the line through the point that cuts off the least ...

geometry - Point P is on the number number line. The distance between O and P is...

math - I need help with this question. Write the equation of the line which ...

Pre-Cal - How do you find the distance from the point to the line given the ...

Mathematics - In an orthonormal system, you're given the following: Point P(1,2...

Maths - In an orthonormal system, you're given the following: Point P(1,2) Lina ...

Physics - The drawing shows four point charges. The value of q is 2.4 µC, and ...