Answer:
B.)4b/a^2
Step-by-step explanation:
21
2
x +
979
21
B) y= -
2
21
x +
979
21
C) y= -
21
2
x + 5
D) y= -
2
21
x +5
Answer:c
Step-by-step explanation:
Answer:
Step-by-step explanation:
To prove the straight line is tangent to the circle:
(1)
substitute x = 2y + 5 into x² + y² = 5
x² + y² = 5
(2y + 5)² + y² = 5
4y² + 20y + 25 + y² = 5
5y² + 20y + 20 = 0
y² + 4y + 4 = 0
(2)
discriminant of y² + 4y + 4 = 0 has to be equals to 0
D = 4² - 4(1)(4)
D = 0
∴ Proven
B. 19.87
C. 19.44
D. 19.43