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If the midpoint of A (a,b) and B (2,-6) is M (-2,6)
Find the value of a then b

User Thequerist
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1 Answer

3 votes

Answer:

a=-6, b=18

Explanation:

The midpoint can be defined as:
M = ((x_1+x_2)/(2), (y_1+y_2)/(2))

The order doesn't matter since addition is associative, just make sure to put them in the right place

So we know what the midpoint is, we can plug in known values to solve for the missing end point.

Let's start with the x-value


-2=(2+a)/(2)

Multiply both sides by 2


-4=2+a

Subtract 2 from both sides


-6=a

Now let's do the y-value


6=(-6+b)/(2)

Multiply both sides by 2


12=-6+b

Add 6 to both sides


18=b

The point is at (-6, 18)

User Tommed
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