Answer:
L = 4πa²b
Step-by-step explanation:
Multiply both sides by 4πa²b.
Answer:
18
Step-by-step explanation:
2πr=36π ⇒ r= 36π/2π= 18
Answer:
<h2>−9a³ − a² + 12a</h2>
Step-by-step explanation:
3a(a²-3a+4)-4(3a³-2a²) = 3a³ − 9a² + 12a − 12a³ + 8a²
= (3a³ − 12a³) + (− 9a² + 8a²) + 12a
= −9a³ − a² + 12a
Answer:
The first plane is moving at 295 mph and the second plane is moving at 355mph.
Step-by-step explanation:
In order to find the speed of each plane we first need to know the relative speed between them, since they are flying in oposite directions their relative speed is the sum of their individual speeds. In this case the speed of the first plane will be "x" and the second plane will be "y". So we have:
x = y - 60
relative speed = x + y = (y - 60) + y = 2*y - 60
We can now apply the formula for average speed in order to solve for "y", we have:
average speed = distance/time
average speed = 1625/2.5 = 650 mph
In this case the average speed is equal to their relative speed, so we have:
2*y - 60 = 650
2*y = 650 + 60
2*y = 710
y = 710/2 = 355 mph
We can now solve for "x", we have:
x = 355 - 60 = 295 mph
The first plane is moving at 295 mph and the second plane is moving at 355mph.
Take everything to one side and equate it to zero
So: 5x^2 -x -1=0
Next factorise so it’s 5(x^2-1/5)-1=0
So: 5(x-1/5) ^2 -1=0
So complete the square
First of all remove the five by division (x- ((1/5)/2)^2+ (1/5/2)^2 ) -1 =0
So (x- 1/10)^2 +1/5 +1/100 =0
Answer is (x-1/10)^2 -21/100 =0
Take -21/100 to the other side so:
(x-1/10)^2 = 21/100
Square root both sides so
(X-1/10) = square root of 21/100
Take -1/10 to the other side so
X= 1/10 + square root of 21/100
