[tex]\angle{B} = 79°[/tex]
Step-by-step explanation:
The sum of all the interior angles of a quadrilateral is 360° so we can write
[tex](14x - 11) + (8x + 7) + (5x + 18) + (10x + 13) = 360[/tex]
[tex]\Rightarrow 37x + 27 = 360[/tex]
Solving for x, we get
[tex]x = 9[/tex]
To find the measure of [tex]\angle{B},[/tex] we use
[tex]\angle{B} = 8x + 7 = 8(9) + 7 = 79°[/tex]
