Answer:
Step-by-step explanation:
Circumference of a circle means the perimeter of a circle and it is given be
Perimeter=2πr
P=2πr
Though π is a constant
But this question want us to find π
Make π the subject of the formula
Then, divide both side by
π=P/2r
Given that P=37.7cm
And diameter =12
And radius is half of diameter.
Therefore, radius =12/2=6cm
Then
π=P/2r
π=37.7/2×6
π=37.7/12.
Then, the last option is the correct option
Answer: x = (sqrt(7) + 2)/3 and
x = ( – sqrt(7) + 2)/3
Explanation:
3x^2 - 4x - 1 = 0
Divide both sides by 3:
3x^2/3 - 4/3x - 1/3 = 0/3
x^2 - 4/3x - 1/3 = 0
x^2 - 4/3x = 1/3
x^2 - 4/3x + (2/3)^2 = 1/3 + (2/3)^2
(x - 2/3)^2 = 1/3 + 4/9
(x - 2/3)^2 = 7/9
Sqrt both sides:
x - 2/3 = sqrt (7/9)
x - 2/3 = |sqrt(7)/3|
Set x -2/3 = sqrt(7)/3
=> x = (sqrt(7) + 2)/3
Set x - 2/3 = - sqrt(7)/3
=> x = ( - sqrt(7) + 2)/3
Answer:
Step-by-step explanation:
The relative speed of the two trains is the sum of the speeds they are traveling. (If you're on either of the trains, this is the speed you appear to be moving when you see the other train.) In our problem, the relative speed of the two trains is 70 mph + 60 mph = 130 mph. What if the trains were traveling in the same direction? Then we'd need to subtract the speed of the slower train from the speed of the faster train, and their relative speed would be 10 mph.
The final answer is
y = -2x - 6