Answer:
d ≈ 14.6 units; M(2.5, 2, 6)
Explanation:
The distance formula for 3 dimensions looks a lot like the one for 2 dimensions:
d = √((x2 -x1)^2 +(y2 -y1)^2 +(z2 -z1)^2)
Filling in the given numbers and doing the arithmetic, you find the distance between the points to be ...
d = √((6-(-1))^2 +(-3-7)^2 +(2-10)^2) = √(49+100+64) = √213 ≈ 14.6
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The midpoint is the average of the end points:
M = ((6, -3, 2) +(-1, 7, 10))/2 = (5/2, 2, 6)