Question

The distance between the points (2,-2) and (-1,x) is 5, one of the value of x is: a)-2 b)2 c)-1 d)1 Answer with solving.

Answer 1

Hey Friend,

Let,

point A = (2,-2)

point B = (-1,X)

Distance AB = 5 units

Applying distance formula,

AB^2 = (x2 - x1)^2 + (y2 - y1)^2

(5)^2 = (-1 - 2)^2 + (X + 2)^2

25 = 9 + X^2 + 4 + 4X 

X^2 + 4X - 12 = 0

X^2 + 6X - 2X - 12 = 0

X(X + 6) -2(X + 6) = 0

(X - 2) (X + 6) = 0

Therefore, 

X = 2   or X = -6

Hope it helps!