Y - 3 = 1/2 (x + 4)
y - 3 = 1/2 x + 2
1/2x + 2 = y - 3
1/2x - y = -3 - 2
1/2x - y = -5 answer
Add then I would divide it
Looking at the two black dots
5 bulbs cost $9
Divide total cost by number of bulbs bought:
9 / 5 = $1.80 per bulb.
10 bulbs cost $18
Divide total cost by number of bulbs bought:
18 / 10 = $1.80 per bulb
The cost for one bulb is $1.80
Answer:

Step-by-step explanation:
Let
, we proceed to transform the expression into an equivalent form of sines and cosines by means of the following trigonometrical identity:
(1)
(2)
Now we perform the operations: 



(3)
By the quadratic formula, we find the following solutions:
and 
Since sine is a bounded function between -1 and 1, the only solution that is mathematically reasonable is:

By means of inverse trigonometrical function, we get the value associate of the function in sexagesimal degrees:

Then, the values of the cosine associated with that angle is:

Now, we have that
, we proceed to transform the expression into an equivalent form with sines and cosines. The following trignometrical identities are used:
(4)
(5)




If we know that
and
, then the value of the function is:


5 is 1/40 of 200.
Therefore, 35 is 7/40 of 200.
7/40 = (17.5)/100. Therefore, 35 is 17.5% of 200.
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To make life easier. Just say that 35/200 =17.5/100.
So 35 is 17.5% of 200.