Find the point on the line 7x+4y-2=0 which is closest to the point (-5,-6).
i get y=(2-7x)/4 and plugged into distance formula:
d=sqrt((x+5)^2+((2-7x)/4+6)^2)
Taking the derivative of this seems like it would be a mess. did i do something wrong?
i get y=(2-7x)/4 and plugged into distance formula:
d=sqrt((x+5)^2+((2-7x)/4+6)^2)
Taking the derivative of this seems like it would be a mess. did i do something wrong?
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Square both sides before taking derivative,
d^2 = (x+5)^2+((2-7x)/4+6)^2
Take derivative with respect to x,
2dd' = 2(x+5) + 2((2-7x)/4+6)(-4/7)
Solving d' = 0 gives you the answer.
Can you finish?
d^2 = (x+5)^2+((2-7x)/4+6)^2
Take derivative with respect to x,
2dd' = 2(x+5) + 2((2-7x)/4+6)(-4/7)
Solving d' = 0 gives you the answer.
Can you finish?
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1) Convert to slope-intercept form.
4y=-7x-2.
2) Solve for y.
y= -7/4x-1/2 (2/4 reduced)
3) I would graph the point (-5, -6) and then graph the line and find the coordinate closest to (-5, -6)
4y=-7x-2.
2) Solve for y.
y= -7/4x-1/2 (2/4 reduced)
3) I would graph the point (-5, -6) and then graph the line and find the coordinate closest to (-5, -6)