the answer is 0.000000007
Answer:
C. The 6th term is positive/negative 80
Step-by-step explanation:
Given
Geometric Progression


Required

To get the 6th term of the progression, first we need to solve for the first term and the common ratio of the progression;
To solve the common ratio;
Divide the 7th term by the 5th term; This gives

Divide the numerator and the denominator of the fraction by 40
----- equation 1
Recall that the formula of a GP is

Where n is the nth term
So,


Substitute the above expression in equation 1
becomes


Square root both sides

r = ±
Next, is to solve for the first term;
Using 
By substituting 160 for T5 and ±
for r;
We get


Multiply through by 16



Now, we can easily solve for the 6th term
Recall that the formula of a GP is

Here, n = 6;



r = ±
So,
or 
or 
or 
±80
Hence, the 6th term is positive/negative 80
If you would like to simplify <span>7 - 3[(n^3 + 8n) / (-n) + 9n^2], you can do this using the following steps:
</span>7 - 3[(n^3 + 8n) / (-n) + 9n^2] = 7 - 3[(-n^2 - 8) + 9n^2] = 7 - 3[-n^2 - 8 + 9n^2] = 7 - 3[ - 8 + 8n^2] = 7 - 3[8<span>n^2 - 8] = 7 - 24n^2 + 24 = - 24n^2 + 31
</span>
The correct result would be <span>- 24n^2 + 31.</span>
Answer: the two trains will meet in 2.8 hours
Step-by-step explanation:
Step 1
Speed of train A = 90mph
Speed of train B = 110 mph
Since both trains are travelling towards each other
, their effective speed will be= 90 mph + 110mph= 200mph
Step 2
we know that Speed = distance / time
therefore Time = Distance / speed
Distance = 560 miles
Speed = 200 mph
Time = 560miles / 200mph
2.8 hours
Answer:
The other angle would be equal to 133 degrees.
Step-by-step explanation:
All linear pairs are supplementary angles, which means that they are equal to 180. So we can find the second angle by using the following angle.
47 + x = 180
x = 133