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Distance between A (2, -1) and (2,a) is 4 units. Find the value of a where a is positive.

User Dafeda
by
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1 Answer

5 votes

Answer:

a = 3

Explanation:

Calculate the distance d using the distance formula and equate to 4

d =
\sqrt{(x_(2)-x_(1))^2+(y_(2)-y_(1))^2 }

with (x₁, y₁ ) = (2, - 1) and (x₂, y₂ ) = (2, a)

d =
√((2-2)^2+(a+1)^2) =
√(0+(a+1)^2) =
√((a+1)^2) = a + 1 then

a + 1 = 4 ( subtract 1 from both sides )

a = 3

User Sajoshi
by
7.4k points