The answer is 8.6. I hope this helped you out!
Im not sure but...
(x+21) + (2x+9)=90
x+21+2x+9 = 90
3x+30 = 90
3x = 60
x = 20
17.83 times 1.1
=19.613
17.83+19.613
=37.443
=37.5 dollars
Let the number be the variable x
4 times the number is 4x
the sum of 8 and 4 times a number is 28
4x+8=28
4x=28-8
4x=20
x=20/4
x=5
? should be the angle measure of the arc.
