SOLUTION: find the distance from(-6,6) to the line defined by y=2x+3 express as a radical or a number rounded to the nearest hundredth

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Question 1149120: find the distance from(-6,6) to the line defined by y=2x+3 express as a radical or a number rounded to the nearest hundredth
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Distance from point (-6,6) to (0,3)

Answer by ikleyn(52797) About Me  (Show Source):
You can put this solution on YOUR website!
.

There is a remarkable formula to calculate the distance from a given point to a given straight line in a coordinate plane.


    Let the straight line in a coordinate plane is defined in terms of its linear equation 

         a*x + b*y + c = 0,

    where "a", "b" and "c" are real numbers, and let P = (x%5B0%5D,y%5B0%5D) be the point in the coordinate plane. 

    Then the distance from the point P to the straight line is equal to

        d = abs%28a%2Ax%5B0%5D+%2B+b%2Ay%5B0%5D+%2B+c%29%2Fsqrt%28a%5E2+%2B+b%5E2%29.


Regarding this formula, see the lesson
    The distance from a point to a straight line in a coordinate plane
in this site.


Your straight line is 2x - y + 3 = 0.


Substitute the given data  a= 2, b= -1, c= 3,  x%5B0%5D = -6,  y%5B0%5D= 6  into the formula to get the distance under the question


    abs%282%2A%28-6%29+%2B+%28-1%29%2A6+%2B+3%29%2Fsqrt%282%5E2%2B%28-1%29%5E2%29 = abs%28-15%29%2Fsqrt%285%29 = 15%2Fsqrt%285%29 = %2815%2Asqrt%285%29%29%2F5 = 3%2Asqrt%285%29 = 6.71  (approximately - rounded as requested).


Answer.  The distance is  3%2Asqrt%285%29 = 6.71  (approximately - rounded as requested).



    

    Straight line  a%2Ax%2Bb%2Ay%2Bc=0,
    the point  P(x%5B0%5D,y%5B0%5D)  and the distance d
    from the point  P  to the straight line

Solved.