Read and write the equation of a circle
Grade 10 Math Worksheet - Challenge Me

Circle the best answer.
Ari draws a round clock face on a grid. A diameter runs from D(-2, 1) to F(4, 9). Which equation is the circle?
- (x − 1)² + (y − 5)² = 25
- (x − 1)² + (y − 5)² = 100
- (x + 1)² + (y + 5)² = 25
- (x + 2)² + (y − 1)² = 100
Bo draws a round pizza on a grid. A diameter runs from D(1, -3) to F(7, 5). Which equation is the circle?
Use the picture in question 1.
- (x − 1)² + (y + 3)² = 100
- (x − 4)² + (y − 1)² = 25
- (x + 4)² + (y + 1)² = 25
- (x − 4)² + (y − 1)² = 100
Esme draws a round pond on a grid. A diameter runs from D(-1, 4) to F(7, 4). Which equation is the circle?
Grid: D, F and the right triangle under DF. Grid: D, F and the right triangle under DF. D F - (x + 3)² + (y + 4)² = 16
- (x − 3)² + (y − 4)² = 16
- (x + 1)² + (y − 4)² = 64
- (x − 3)² + (y − 4)² = 64
Jun draws a sun shape in a mural on a grid. A diameter runs from D(0, 1) to F(2, 5). Which equation is the circle?
Grid: D, F and the right triangle under DF. Grid: D, F and the right triangle under DF. D F - (x + 1)² + (y + 3)² = 5
- (x − 1)² + (y − 3)² = 5
- x² + (y − 1)² = 20
- (x − 1)² + (y − 3)² = 20
Grid: the circle with its center marked. Grid: the circle with its center marked. Kira draws a drum top on a grid as (x − 3)² + (y + 1)² = 16. Which inequality gives its domain (all its x-values)?
- -1 ≤ x ≤ 7
- -13 ≤ x ≤ 19
- -7 ≤ x ≤ 1
- -5 ≤ x ≤ 3
Noah draws a round cake on a grid as (x + 2)² + (y + 6)² = 36. Which inequality gives its range (all its y-values)?
Use the picture in question 5.
- 0 ≤ y ≤ 12
- -8 ≤ y ≤ 4
- -12 ≤ y ≤ 0
- -42 ≤ y ≤ 30
Grid: a circle through (1, 3), (-2, 6), (-5, 3) and (-2, 0); its center is not labeled. Pia traces a round clock face on a grid. Which equation matches the drawing?
Grid: a circle through (1, 3), (-2, 6), (-5, 3) and (-2, 0); its center is not labeled. Grid: a circle through (1, 3), (-2, 6), (-5, 3) and (-2, 0); its center is not labeled. x y (1, 3) (-2, 6) (-5, 3) (-2, 0) 0 - (x + 2)² + (y − 3)² = 3
- (x − 1)² + (y − 3)² = 9
- (x − 2)² + (y + 3)² = 9
- (x + 2)² + (y − 3)² = 9
Ren traces a round pizza on a grid. Which equation matches the drawing?
Grid: a circle through (9, -1), (4, 4), (-1, -1) and (4, -6); its center is not labeled. Grid: a circle through (9, -1), (4, 4), (-1, -1) and (4, -6); its center is not labeled. −10 −8 −6 −4 −2 2 4 6 8 10 −10 −9 −8 −7 −6 −5 −4 −3 −2 −1 1 2 3 4 5 6 7 8 9 10 - (x − 4)² + (y + 1)² = 25
- (x − 9)² + (y + 1)² = 25
- (x − 4)² + (y + 1)² = 5
- (x + 4)² + (y − 1)² = 25
Tala traces a round pond on a grid. Which equation matches the drawing?
Grid: a circle through (5, 2), (1, 6), (-3, 2) and (1, -2); its center is not labeled. Grid: a circle through (5, 2), (1, 6), (-3, 2) and (1, -2); its center is not labeled. (5, 2) (1, 6) (-3, 2) (1, -2) x y - (x − 1)² + (y − 2)² = 16
- (x − 5)² + (y − 2)² = 16
- (x − 1)² + (y − 2)² = 4
- (x + 1)² + (y + 2)² = 16
Zee traces a sun shape in a mural on a grid. Which equation matches the drawing?
Grid: a circle through (-1, -5), (-3, -3), (-5, -5) and (-3, -7); its center is not labeled. Grid: a circle through (-1, -5), (-3, -3), (-5, -5) and (-3, -7); its center is not labeled. Grid −6 −5 −4 −3 −2 −1 0 −8 −7 −6 −5 −4 −3 −2 - (x + 3)² + (y + 5)² = 2
- (x + 3)² + (y + 5)² = 4
- (x + 1)² + (y + 5)² = 4
- (x − 3)² + (y − 5)² = 4