Answer:
Step-by-step explanation:
x² - 2x + y² - 4y - 4 = 0
x² - 2x + y² - 4y = 4
complete the squares
(x² - 2x + x₀) + (y² - 4y + y₀) = 4
the unknown number will be the square of half of the x¹ coefficient
(x² - 2x + 1) + (y² - 4y + 4) = 4 + 1 + 4
(x - 1)² + (y - 2)² = 9
This tells us that the circle is centered on (1, 2)
Which is also a point on the diameter
2x - y + a = 0
a = y - 2x
a = 2 - 2(1)
a = 0
Answer:
The third answer is the correct one.
Answer:
8 - 
Step-by-step explanation:
For this problem you have to use the 45-45-90 triangle theorem and 30-60-90 theorem.
For 45-45-90, the isosceles sides = 4, so the hypotenuse of the 30-60-90 triangle is 4 times 2, which is 8. If x is 8, then since y is the side across from the 60 angle, y is 
. Since this really can't be simplified after y is subtracted from x, the final answer is just 8 - .
