Both 25x and 22x + 9 have the same answers. So you set those two equal to each other.
Subtract 22x from both sides.
and you're left with this.
Next, divide 3 from both sides.
re-insert 3 into one of the equations.
add up both angles
all angles (for quadrilaterals)added up equals 360.
solve for x. Subtract 150 from both sides.
and divide 2 from both sides
AngleLMN= 105