Answer:
9pr = 2q^2
Step-by-step explanation:
28.
px^2 + qx + r = 0
If one root is A then the other root is 2A
We have A + 2A = -q/p and A*2A = r/p
So 3A = -q/p so A = -q/3p and A^2 = r/2p so A = √ (r / 2p)
Equating these 2 equations:-
-q/3p = √(r / 2p)
q^2 / 9p^2 = r / 2p
9p^2r = 2pq^2
9pr = 2q^2 (answer)
Answer:
x^2+6x-4=0 x^2+6x=4 x^2+6x+9=13 (x+3)(x+3)=13 x+3=+or-(13^1/2) x=-3+or-13^1/2
Step-by-step explanation:
sry if im wrong :< if im right, can i have brainliest? have a wonderful day/night :D
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
Answer:
26.25 gallons
Step-by-step explanation:

21000 = 800x
x = 26.25 gallons