Question

The angle of elevation of the top of the first story buildingis 30 degree at a point on the ground distant 15 m from its foot how high its second story will be if the angle of elevation of the top of the second story building at the same pint is 45 degree

Answer 1

Statement:-   let AC be the building with two storeys bottom one as BC and the top one as AB. there is a point D from foot of building 15m away from foot of the building. Angle of elevation to the top of the first storey is 30° and the angle of elevation to the top of the second storey is 45°. we are interested to find the height of the top  of the second storey.
In right triangle ACD
tanФ= perpendicular/base
tan45°= AC/15
    1/1        =AC/15
 AC= 15 m
Thus 15 m is the height of the top of the second storey from the foot of building