Answer:
y = 6
Step-by-step explanation:
Given that y varies directly with x then the equation relating them is
y = kx ← k is the constant of variation
To find k use the condition y = 3 when x = 9, then
k =
=
=
, thus
y =
x ← equation of variation
When x = 18, then
y =
× 18 =
= 6
Answer:
a = - 4
Step-by-step explanation:
Given x = - 2 is a root then f(- 2) = 0
f(x) = x³ + x² + ax - 4, thus
f(- 2) = (- 2)³ + (- 2)² - 2a - 4 = 0, that is
f(- 2) = - 8 + 4 - 2a - 4 = 0, thus
- 8 - 2a = 0 ( add 8 to both sides )
- 2a = 8 ( divide both sides by - 2 )
a = - 4
![6n+9=-3-21-6](https://tex.z-dn.net/?f=6n%2B9%3D-3-21-6)
subtract the numbers:
![-3-21-6=-30](https://tex.z-dn.net/?f=-3-21-6%3D-30)
![6n+9=-30](https://tex.z-dn.net/?f=6n%2B9%3D-30)
subtract 9 from both sides
![6n+9-9=-30-9](https://tex.z-dn.net/?f=6n%2B9-9%3D-30-9)
simplify
![6n=-39](https://tex.z-dn.net/?f=6n%3D-39)
divide both sides by 6
![\frac{6n}{6}= \frac{-39}{6}](https://tex.z-dn.net/?f=%20%5Cfrac%7B6n%7D%7B6%7D%3D%20%5Cfrac%7B-39%7D%7B6%7D%20)
![n= \frac{-13}{6}](https://tex.z-dn.net/?f=n%3D%20%5Cfrac%7B-13%7D%7B6%7D%20)
decimal
![n=-6.5](https://tex.z-dn.net/?f=n%3D-6.5)
Hope this helps :)
Answer:
10 hours (I am not positive)
Step-by-step explanation:
We first want to find the volume of pool which is 30 x 18 x 4 = 2160.
Then you are going to divide by 216 to find how many hours it takes to drain the whole pool. (I'm not that big of an expert)
Answer: a= -18/2
Step-by-step explanation:
2a + 2x3 = -12
2a + 6 = -12
2a + 6 - 6 = -12 - 6 ( subtract 6 from both sides)
2a = -18 (Divide 2 by both sides)
a= -18/2