The shortest distance between a point and a line is a perpendicular line, which you have already found. There are two ways to do this.
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1). Use the distance formula given by:
d = |y1 - m*x1 - b| / √(m² + 1), where
(x1, y1) = (6,-2), and m and b are the slope and y-intercept of the line.
−2x+4y=0
4y = 2x
y = ½x ---------> m = ½, b = 0
d = |y1 - m*x1 - b| / √(m² + 1)
= |-2 - 3 - 0| / √1.25
= 5/√(5/4)
= 5*√(4/5)
= 5*2/√5
d = 2√5
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2) Find the length of the segment of the perpendicular line y= -2x + 10 from (6, -2) to the intersection of the two lines.
Two lines intersect at a point where they have the same coordinates, so set the two y equations equal to each other and solve for x. Then plug that x into one of the equations to find the y coordinate.
−2x+4y=0 ------------> y = ½x
½x = -2x + 10
2½ x = 10
5/2 x = 10
x = 4
-------> y = ½x = 2
-------> (4, 2) is the intersection point.
So find the distance between the points (6, -2) and (4, 2).
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Verified answer
The shortest distance between a point and a line is a perpendicular line, which you have already found. There are two ways to do this.
*********************************
1). Use the distance formula given by:
d = |y1 - m*x1 - b| / √(m² + 1), where
(x1, y1) = (6,-2), and m and b are the slope and y-intercept of the line.
−2x+4y=0
4y = 2x
y = ½x ---------> m = ½, b = 0
d = |y1 - m*x1 - b| / √(m² + 1)
= |-2 - 3 - 0| / √1.25
= 5/√(5/4)
= 5*√(4/5)
= 5*2/√5
d = 2√5
***********************
2) Find the length of the segment of the perpendicular line y= -2x + 10 from (6, -2) to the intersection of the two lines.
Two lines intersect at a point where they have the same coordinates, so set the two y equations equal to each other and solve for x. Then plug that x into one of the equations to find the y coordinate.
−2x+4y=0 ------------> y = ½x
½x = -2x + 10
2½ x = 10
5/2 x = 10
x = 4
-------> y = ½x = 2
-------> (4, 2) is the intersection point.
So find the distance between the points (6, -2) and (4, 2).
Distance formula:
d = √[(x2 - x1)² + (y2 - y1)²]
= √[(4-6)² + (2 - (-2))²]
= √(4 + 16)
= √20
= 2√5