Here's how it's solved.. ツ
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Hello :
<span>Cos θ = -3/5
sin</span>θ = - 4/5
because : Cos² θ +sin²θ = (-3/5)²+(-4/5)2 =9/25+16/25 = 25/25 = 1
and θ is in QIII.where : sinθ <span>< 0</span>
Answer:
<u>The equations system is:</u>
<u>x + y = 10</u>
<u>0.5x + 0.9y = 6</u>
Step-by-step explanation:
1. Let's review the information given to us to answer the question correctly:
Liters of 60% acid solution needed = 10
x = Number of liters of the 50% solution
y = Number of liters of the 90% solution
2. Which equation represents the total liters of acid that are needed?
There are two equations needed:
The first one related to the total liters needed, 10 in this case:
x + y = 10
The second one related to the acid concentration of the 10 liters:
0.5x + 0.9y = 10 * 0.6
0.5x + 0.9y = 6
<u>The equations system is:</u>
<u>x + y = 10</u>
<u>0.5x + 0.9y = 6</u>
Solving for x and y in the 2nd equation, we have:
0.5 (10 - y) + 0.9y = 6
5 - 0.5y + 0.9y = 6
0.4y = 6 - 5
0.4y = 1
y = 1/0.4 = 2.5 ⇒ x = 7.5 (10 - 2.5)
The scientist can mix 7.5 liters of the 50% acid solution and 2.5 liters of the 90% acid solution to get the 10 liters of the 60% acid solution.
Answer:
x = 9
Step-by-step explanation:
because the angle is the same as 45 degrees
Answer:
2d(d³-9d-30)
Step-by-step explanation:
2d⁴ - 6d - 18d² - 54d
= 2d⁴- 18d²-60d
=2d(d³-9d-30)