Answer:
12
Step-by-step explanation:
I attached a picture, see if you can see what I'm doing. Basically, I start by squaring everything to get rid of the radical, but just remember at the end to always, always check your answers, because squaring your answers could get rid of some negative numbers that could result in imaginary answers. The answer I came up with was a=5,-2
I don’t think this is the full question
Answer: (x + 6)² + (y + 5)² = 17
Explanation:
1) The equation of a circle is: (x - a)² + (y - b)² = r², wnere:
a is the x-coordinate of the center of the circleb is the y-coordinate of the center of the circler is the radius of the circle
2) Since the points (-7,-1) and (-5,9) define a diameter, you can find the center of the circle as the mid point of the diameter:
x-coordinate of the mid point = (-7 - 5) / 2 = - 12 / 2 = - 6
y-coordinate of the mid point = (-9 - 1)/ 2 = - 10 / 2 = - 5
Therefore, the center of the circle is (-6,-5)
3) The radius of the center is half the diameter.
The length of the diameter is found using the formula for the distance between two points applied to the two endopoints given:
diameter² = (7 - 5)² + (- 1 + 9)² = 2² + 8² = 4 + 64 = 68
⇒diameter = √68 = 2√17
⇒ radius = diamter / 2 = 2√17 / 2 = √17
4) Now you can replace the coordinates of the center and the radius into the equation:
(x + 6)² + (y + 5)² = 17
9514 1404 393
Answer:
(√7)/3
Step-by-step explanation:
The relationship between tangent and cosine is ...
tan(α) = √(1/cos(α)² -1)
The cosine of the angle is given as 3/4, so the tangent is ...
tan(arccos(3/4)) = √(1/(3/4)² -1) = √(16/9 -1) = √(7/9)
tan(arccos(3/4)) = (√7)/3