Two angles are complementary when their sum is equal to 90°.
So, ( 2x + 39 ) + ( 7x - 21 ) = 90°
9x + 18° = 90°
x = 8°
Putting value of x in the angles given :
( 2x + 39 )° = 2(8°) + 39° = 55°.
( 7x - 21 )° = 7(8°) - 21° = 35°.
Therefore, the angles are 55° and 35°.
Hence, this is the required solution.
4 1/2 + 3 2/3 = 8.16666667
Due to the inclination of the
terrestrial axis, the day has different duration in several points of the
planet, which also depends on the time of year. However, this duration remains the same throughout the year in the Equator,
which is known as the imaginary line that divides the planet in two
hemispheres: Northern Hemisphere and Southern Hemisphere.