Answer: 45?
Step-by-step explanation: Sorry If I'm wrong, I haven't learned this yet but I tried my best.
The answer is D
U would subtract a^2 then square both sides to isolate the variable
As shown in the figure
Height of helicopter above the ground=30 m
Distance from the base to the point where the person is standing=30 m
height of the person=2 m
Now the person cast the shadow of length x m.
Triangle ABC and triangle EDC are similar.
∵ ∠B= ∠D=90°
∠C is common.
So by AA similarity ΔABC and ΔEDC are similar.
As we know when triangles are similar their sides are proportional.
AB/AD =BC/DC
Let DC=x meter
⇒![\frac{10}{x}=\frac{30+x}{x}](https://tex.z-dn.net/?f=%5Cfrac%7B10%7D%7Bx%7D%3D%5Cfrac%7B30%2Bx%7D%7Bx%7D)
⇒5=\frac{30+x}{x}[/tex]
⇒5x=30+x
⇒4x = 30
⇒ x=30/4
⇒ x=7.5 meter
So length of shadow=7.5 meter
2. volume of a sphere of radius r is v (r) =![\frac{4}{3}π r^{3}](https://tex.z-dn.net/?f=%5Cfrac%7B4%7D%7B3%7D%CF%80%20r%5E%7B3%7D)
=4/3π×3![r^2](https://tex.z-dn.net/?f=r%5E2)
=4π![r^2](https://tex.z-dn.net/?f=r%5E2)
surface area of a sphere of radius r is 4π![r^2](https://tex.z-dn.net/?f=r%5E2)
b) Ratio of derivative of volume of sphere to surface area of sphere=![\frac{4\pi r^2}{4\pi r^2}](https://tex.z-dn.net/?f=%5Cfrac%7B4%5Cpi%20r%5E2%7D%7B4%5Cpi%20r%5E2%7D)
=1 [ incomplete question but you have written few words ]
Answer:
Open circle. Points right
Step-by-step explanation:
The reason for it is because this symbol > represents greater than when it comes to inequalities. When it is an open circle that means that you are not including the number. So that also means that the -2.5 is not included to the inequality equation but it can be any other number other than that number.
The answer for your question is 4x^2-15x+6+ 2/3x+5