Question

Point A is at (-7,-7) and point M is at (-6,-1). Point M is the midpoint of point A and B. What are the coordinates of point B?

Answer 1

Answer:

(-5,5)

Step-by-step explanation:

For point (x1,y1) and (x2,y2) on a coordinate plane ,

coordinate of midpoint is given by (x1+x2)/2, (y1+y2)/2

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In the problem

point A(-7,-7)

let point B be (x,y) thus

midpoint point M for AB will be (-7+x)/2, (-7+y)/2

It is given that M is(-6,-1)

hence  (-7+x)/2, (-7+y)/2 will be same as (-6,-1)

Thus,

(-7+x)/2 = -6            and  (-7+y)/2 = -1

=> -7+x = -6*2                =>  -7+y = -1*2

=> -7+x = -12                  => -7+y = -2

=> x = -12+7                   => y = -2+7

=> x = -5                        => y = 5

Thus, coordinates of point B is (x,y) = (-5,5)