Step-by-step explanation:
By Cosine rule, we have
s² = t² + u² - 2(t)(u)(cosS)
=> cosS = (t² + u² - s²)/2tu
=> cosS = (58² + 27² - 50²) / (2 * 58 * 27) = 0.5086.
Therefore S = cos^-1(0.5086) = 59.4° (1d.p.)
Answer:
Step-by-step explanation:
do it your self
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)
The answer is D, 8$. One easy way to do it is to take 10% of 40, which is 4, and double it.