xmagedo wrote:
In the xy plane, point p has coordinates (a,b) and point Q has coordinate(c,d). What is the distance between point Q ?
1 b-d=4
2 a-c=3
I dont understand this type of question, I mean the xy plane ! so if there a formula to follow in case then someone help me out
thanks
Distance between point \(A(x_1,y_1)\) and \(B(x_2,y_2)\) can be found by the formula \(D=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}\).So the distance between point \(P(a,b)\) and point \(Q(c,d)\) would be \(D=\sqrt{(a-c)^2+(b-d)^2}\).
(1) b-d=4 --> don't know a-c. Not sufficient.
(2) a-c=3 --> don't know b-d. Not sufficient.
(1)+(2) We have all necessary info. Sufficient: \(D=\sqrt{(a-c)^2+(b-d)^2}=\sqrt{3^2+4^2}=5\).
Answer: C.
For more on this topic check Coordinate Geometry chapter of Math Book (link in my signature).
Hope it helps.
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