confusion qns - help thanks (1 Viewer)

[bos1234]

Is the first one correct method for proving/need help on others

Diagram for last question:

thanks bye

 

[z600]

x>squareroot(9-y^2)

First rearranged it to x^2+y^2=9 (consider equality)
Here you have loss of information which you will deal with later.

Draw that, its a circle with radius of 3

since it is squaroot, rub out anything below the x axis. (from the loss of information, a squaroot cant not have a negative result)
Make the function line dotted, and shade in the region outside of the circles (this is because of the > sign. )

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For the ballon one, draw a perpendicular line from the balloon down to the road. Thus splitting the top angle into 2.

First one is 180-(90+57)= 33
Second one is 180-(90+33)= 57

When u drew that perpendicular line, you divided the road into 2, name it x and y.
Let the height be h

x+y=1
Tan 57=h/x
tan35=h/y

Rearrange them to let x and y be the subject.
then add the two and they should =1

i got

h/tan 57+h/tan 35=1

and solve, i got apx 240metres ( i did it quickly, might have made a mistake)

You can also solve it using the sine rule.

 

[bos1234]

ok thanks for that one.

Someone also on the other ones

thanks bye

 

[SoulSearcher]

Yeah, first method should be fine.
Second question, square both x and y, then add x² and y² together.