Question 326743
The definition of a complementary angles is that the sum of the angles is equal to 90. thus we have the ratio 4:5. We then set up the problem as follows 4x + 5x=90. Then you would add (4+5)x=9x    9x=90   divide both sides by 9 and x is equal to 10. Then we go back and multiply to find the value of each angle. ie

4(x)=4(10)=40         5(x)=5(10)=50.   The angle values are 40 and 50.