
Mark M. answered 04/28/15
Tutor
5.0
(243)
Mathematics Teacher - NCLB Highly Qualified
F = fourth angle
F = 360 - 60 - (10y - 9) - (9y - 7)
F = 300 - 10y + 9 - 9y + 7
F = 300 - 19y + 16
F = 316 - 19y