Step-by-step answer:
The first step in solving a problem of geometry and trigonometry is to draw a diagram, with all the given information in it. The attached image does just that.
Here, we have (horizontal) distance of building to the tower is 400'.
We see two right triangles, each with a leg of 400' (horizontal).
The vertical distances are denoted h1 and h2 for the angles of elevation 24 and 20 degrees respectively.
Using the definition of tangent, we have
h1= 400tan24=178.1
h2=400tan20=145.6
The height of the tower is therefore h1+h2=178.1+145.6=323.7 feet
To find 1/3 of 27 divide 27 by the denominator (which in this case would be 3) then multiply by the numerator (which is one) so you'd do 27 divided by 3 then multiply by 1
First you cross multiply.
2*(b-4)=6b
Then distribute the 2.
2b-8=6b
Minus 2b from each side.
-8=4b
Divide each side by 4.
-2=b
So -2 is your answer.