Coordinate Geometry

Question 1

Give an equation of a straight line (provided that you have two coordinate points on it, or at least 1 and a coordinate)

Answer 1

y−y’1’ =(x−x’1’)(y’2’ -y’1’)/(x’2’-x’1’)=(x−x’1’)m

Question 2

How are the coordinates of the centre of a circle represented?

Answer 2

(a,b)

Question 3

What’s the equation of a circle?

Answer 3

(x-a)^2 + (y-b)^2 = r^2

Question 4

What would you get if you timesed together the gradients of 2 perpendicular lines?

Answer 4

-1

Question 5

Give the three possible options for the intersections of 2 straight lines.

Answer 5

1 unique solution (intersection); no solutions (parallel and not option 3); infinite solutions (on top of each other)

Question 6

you plug some coordinates into the equation of a circle, give me the 3 options of your answer

Answer 6

(Ans< r^2) this coordinate lays inside the circle; (Ans= r^2) this coordinate lays on the circle; (Ans> r^2) this coordinate lays outside the circle

Question 7

1 straight line, 1 circle. What might be suggested by these intersections?

Answer 7

no touching? b^2-4ac<0. No solution; Tangent? Repeated roots!; 2 points of intersection? You are probably looking at a quadratic equation.