Math Circles

What is the coordinate on the unit circle at 30⁰?

• (1/2, √3/2)

• (√3/2, 1/2)

• (√2/2, √2/2)

• (√2/2, 1/2)

Tags

CCSS.HSF.TF.A.2

You start on the unit circle at (0, -1) and move 300° counterclockwise. Which angle (in degrees) will you end up on the unit circle?

• 30

• 330

• 210

• 120

Find the x intercepts of the graph of the circle given by the equation

x ² + 3x + y ² - 4y = 18

Write the intercepts as coordinates

Find an equation of the circle whose center is at the point (2 , -5) and is tangent to the x axis.

Tags

CCSS.HSG.GPE.A.1

What is the equation of the circle, with centre (-4,5) and radius 6 units?

• (x - 4)^2 + (y + 5)^2 = 6

• (x - 4)^2 + (y + 5)^2 = 36

• (x + 4)^2 + (y - 5)^2 = 6

• (x + 4)^2 + (y - 5)^2 = 36

Tags

CCSS.HSG.GPE.A.1

Determine the center and radius:
x² + y² - 10x + 8y -8 = 0

• C = (5,-4) r = 7

• C = (-5,4) r = 7

• C = (-4,5) r = 49

• C = (5,-4) r = 49

Tags

CCSS.HSG.GPE.A.1

What is the radius of the circle with this equation of  (x-5)²+(y+7)²=8?

• 4

• 8

• 4√2

• 2√2

Tags

CCSS.HSG.GPE.A.1

What is the formula for circumference of a circle given the diameter?

• C = pi x radius

• C = pi x 2radius

• C = pi x diameter

• C = pi x 2diameter

Tags

CCSS.7.G.B.4

Circle O has a center at (3,1) and a diameter of 10 units. Which point lies on circle O?

• (3,-4)

• (-3,-1)

• (5,1)

• (8,0)

Tags

CCSS.HSG.GPE.A.1

Find an equation of the circle whose diameter has endpoints at (-5 , 2) and

(3 , 6).

Tags

CCSS.HSG.GPE.A.1