Geometry Quiz

What is the equation of a circle centred at the origin?

• x^2 + 2gx + y^2 + 2fy + c = 0

• x^2 + 2gx + y^2 + 2fy + c = 0

• x^2 + y^2 = r^2

• x^2 - 2ax + y^2 - 2by + a^2 + b^2 - r^2 = 0

What is the general equation of a circle?

• x^2 + y^2 = r^2

• x^2 + 2gx + y^2 + 2fy + c = 0

• x^2 - 2ax + y^2 - 2by + a^2 + b^2 - r^2 = 0

• x^2 + 2gx + y^2 + 2fy + c = 0

How can you find the equation of the tangent to a circle through a given point on its circumference?

• Calculate the area under the curve

• Calculate the gradient of the radius

• Calculate the gradient of the tangent

• Calculate the circumference of the circle

What is the equation of the tangent at the point (0,2) to the circle x^2 + y^2 - 4x + 2y - 8 = 0?

• y = 2x + 1

• y = 3x

• y = -2x

• y = x - 5

What are the points of intersection of the line y = 2x + 1 and the circle x^2 + y^2 - 2y + 4 = 0?

• (4,2) and (2,6)

• (1,3) and (-1,-1)

• (1,2) and (2,-1)

• (2,-1) and (0,1)