Question

Find the value for which the distance the point P (2,-3) and
Q (10,y) is 10 units​

Answer 1

the formula to calculate the distance between two points (a,b) and (c,d) is given by

dist d = √(a-c) + (b-d)² applying it for this ques we have

d-10 units 10

= √(2 - 10)²+ (-3-y)²

squaring both sides

100 = (-8)²+ (9 + y²+ 6y)

100 = 64 +9 + y² + 6y

y + 6y - 27 = 0

y + 9y - 3y - 27 = 0

y(y + 9) -3(y + 9) = 0

(y-3)(y+9) = 0

y=3 or y=-9

both values of y are possible unless no other condition is specified in the question.