Answer
x=10$^{\circ}$
m$\angle$4=110$^{\circ}$
Work Step by Step
m$\angle$3=m$\angle$6
$x^{2}$-3x=(x+4)(x-5)
$x^{2}$-3x=$x^{2}$-x-20
-2x=-20
x=10$^{\circ}$
m$\angle$4=180-m$\angle$3
m$\angle$4=180-($(10)^{2}$-3(10))
m$\angle$4=180-70
m$\angle$4=110$^{\circ}$
