IF THE ANGLE OF ELEVATION OF A FROM B IS 42°, WHAT IS THE ANGLE OF DEPRESSION OF B FROM A?.

138°

Step-by-step explanation:

The angle of elevation and depression are supplementary, thus

angle of depression = 180° - 42° = 138°

Angle of depression = 138 degrees

Step-by-step explanation:

Angle of elevation = 42 degrees

Angle of depression = ?

To find the angle of depression, We'll simply subtract the angle of elevation from 180 degrees because angle of elevation and angle of depression add up to 180 degrees.

So,

Angle of depression = 180-42

Angle of depression = 138 degrees

check the picture below.

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.