<span>x² - 18x - 4 = ox² - 18x = 4x² - 18x + (18/2)² = 4 + (18/2)²x² - 18x + 81
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Answer:
5) arccos A = 28°
6) arcsin A = 53°
Step-by-step explanation:
5) cos A = 30/34
6) sin A = 32/40
Answer: x=7.5
Step-by-step explanation:
This is the concept of algebra, to calculate the proportion of wool in each item we proceed as follows;
Let the amount of wool used for hat be x
amount of wool in sweater will be 5x
the amount of wool used in scarf will be x-5
therefore the total amount of wool will be:
x+5x+(x-5)=550
x+5x+x-5=550
7x-5=550
7x=550+5
7x=555
hence;
x=555/7
x=79
the amount used in hat x=79g
amount used in sweater 5x=395g
amount used in scarf=79-5=74g
Answer:
a = 195 ; c = 615
Step-by-step explanation:
So, you want to start by forming your equations...
I will use 'c' for children and 'a' for adults for my variables
3a + 30 = c
(this is because of the info that 30 more tickets than 3 times the amount of children's were sold than adult)
then for equation 2:
3c + 5a = 2820
(this is because of the prices of the tickets and the total money raised)
Then, plug in the equation for c
Your equation should look like:
3(3a + 30) + 5a = 2820
You get:
(9a +90) + 5a = 2820
Then:
14a = 2730
So:
a = 195 adult tickets sold
Plug in a, to find c:
3 (195) + 30 = c
585 + 30 = c
c = 615 children tickets sold