Help please number 11

To begin, you need to know that complementary angles add up to 90 degrees.
Therefore, E + F = 90. Now plug it in:
(x - 10) + (x + 2) = 90
Then, combine like terms:
2x - 8 = 90
Add 8 on both sides:
2x = 98
Finally, divide by 2 on both sides:
x = 49
But it doesn't end there! You need to plug x into each angle to find both! So:
E = 49 - 10
E = 39.
F = 49 + 2
F = 51.