To find the measure of angle ∠F, we need to understand that vertical angles are always congruent. Therefore, ∠D = ∠F and we can equate their measures:
m∠D = m∠F
4x + 8 = x + 17
Now, let's solve for x:
3x = 9
x = 3
Substitute the value of x back into the equation for ∠F:
m∠F = 4x + 8 = 4(3) + 8 = 12 + 8 = 20
Therefore, the measure of angle ∠F is 20 degrees.