Answer:
800
Step-by-step explanation:
d=2r=2·400=800
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
⇒
⇒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) =
=4/3π×3
=4π
surface area of a sphere of radius r is 4π
b) Ratio of derivative of volume of sphere to surface area of sphere=
=1 [ incomplete question but you have written few words ]
Subtract C in both sides:
2c + 1 = 1
Subtract 1 on both sides
2c = 0
The solution is:
x = 0
Hope this helped
Answer:
No mistake
Step-by-step explanation:
2x + y = 5
x - 2y = 10
y = 5 - 2x
x - 2(5 - 2x) = 10
x - 10 + 4x = 10
5x - 10 = 10
5x = 20
x = 4
2(4) + y = 5
y = -3
She made no mistake
You can check by plugging in x = 4 and y = -3 into the original equations . They fit exactly.
ABC = 408
C + 7 = B
A + 5 = B
B - 7 + B - 5 + B = 408
3B - 12 = 408
+ 12 = +12
3B = 420
/3 = /3
B = 120
A = 115
C = 113
The answer is A = 115, Abel has $ 115