Please Help!! [ tough geometry question :( ]

Answer: [tex]133^{\circ}[/tex]
Step-by-step explanation:
Opposite angles of a cyclic quadrilateral are supplementary, so:
[tex]4x+5+x+15=180\\\\5x+20=180\\\\5x=160\\\\x=32[/tex]
This means that [tex]m\angle A=4(32)+5=\boxed{133^{\circ}}[/tex]