Since p = x² - 7, you can substitute/plug in p for x² - 7
So:
(x² - 7)² - 4x² + 28 = 5
(p)² - 4x² + 28 = 5 You can factor out -4 from (-4x² + 28)
p² - 4(x² - 7) = 5 Plug in p
p² - 4p = 5 Subtract 5
p² - 4p - 5 = 0 Your answer is C
Step 1
Let n represent car and m represent motorcycles.
n + m = 50 ...................1
car has four wheels and motorcycle has two wheels
4n + 2m = 164 .............................. 2
Step 2
Solve equation 1 and 2 simultaneously.
from (1), make n subject of relation and substitute in equation 2.
n = 50 - m
Step 3
Substitute n in equation 2
4(50 - m) + 2m = 164
200 - 4m + 2m = 164
collect like terms
200 - 164 = 4m - 2m
36 = 2m
m = 36/2
m = 18
next find n
n = 50 - m
n = 50 - 18
n = 32
There are 32 cars and 18 motorcycles.
The length of the rope for this case is given by the length of the circumference.
We have then:
C = 2 * pi * R
Where,
R: Earth radio.
We have then:
C = 2 * pi * (6371)
C = 12742 * pi
Answer:
the length of this rope is:
C = 12742 * pi
