Answer:
B.
Step-by-step explanation:
sin∅ = opposite side over hypotenuse
cos∅ = adjacent side over hypotenuse
To find <em>x</em>, there are multiple ways:
tan72° = 6/x
x = 6/tan72°
cos72° = x/15
15cos72° = x
Answer:
2.8 liters
She drank 2.8 liters all together.
Step-by-step explanation:
0.878+1.2+0.75= 2.8
Using a system of equations, the prices are given as follows:
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
For this problem, the variables are given as follows:
- Variable x: Cost of a reference book.
- Variable y: Cost of an exercise book.
3 reference and 2 exercise cost RM63, hence:
3x + 2y = 63.
5 reference and 3 exercise cost RM102, hence:
5x + 3y = 102.
Multiplying the first equation by 3 and the second by -2, we have that:
Adding them:
-x = -15 -> x = 15.
Hence:
3(15) + 2y = 63
2y = 18.
y = 9.
Hence the costs are:
More can be learned about a system of equations at brainly.com/question/24342899
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Given:
Violinists : Cellists = 7:3.
Number of violinists in the school orchestra = 21
To find:
The combined number of cellists and violinists.
Solution:
Let the number of violinists and cellists in the school orchestra are 7x and 3x respectively.
Then, combined number of cellists and violinists is
...(i)
Number of violinists in the school orchestra = 21
Divide both sides by 7.
Now, the combined number of cellists and violinists is
[Using (i)]
Therefore, the combined number of cellists and violinists is 30.
