Question

A circle has equation x2 + y2 = 25

Answer 1

Answer: A. (5; 0), B. (0; - 5), C. (-5; 0), D. (0; 5).

Step-by-step explanation:

A. (5; _)   [x = 5; y - ?]

x² + y² = 25

5² + y² = 25

25 + y² = 25

25 + y² - 25 = 25 - 25

y² = 0

y = 0

A. (5; 0)

B. (_; -5)   [x - ?; y = -5]

x² + y² = 25

x² + (- 5)² = 25

x² + 25 = 25

x² + 25 = 25

x² + 25 - 25 = 25 - 25

x² = 0

x = 0

B. (0; - 5)

C. (_; 0)   [x - ?; y = 0]

x² + y² = 25

x² + 0² = 25

x² + 0 = 25

x² = 25

x = ± √25 = ± 5

C. (-5; 0) or (5; 0)

Point A has coordinates (5; 0), which means that

point C has coordinates (-5; 0).

D. (0; _)   [x = 0; y - ?]

x² + y² = 25

0² + y² = 25

0 + y² = 25

y² = 25

y = ± √25 = ± 5

D. (0; - 5) or (0; 5)

Point B has coordinates (0; -5), which means that

point D has coordinates (0; 5).