Question

6.1 polygons hw
what is ( mangle b )?
( angle b=)

Explanation:

Step1: Find the sum of interior angles of quadrilateral

The sum of interior angles of a quadrilateral is \((4 - 2)\times180^{\circ}=360^{\circ}\).

Step2: Set up the equation

\((8x + 7)+(5x + 18)+(14x-11)+(10x + 13)=360\).
Combine like - terms:
\((8x+5x + 14x+10x)+(7 + 18-11+13)=360\)
\(37x+27 = 360\).

Step3: Solve for \(x\)

Subtract \(27\) from both sides:
\(37x=360 - 27\)
\(37x=333\)
Divide both sides by \(37\):
\(x=\frac{333}{37}=9\).

Step4: Find \(m\angle B\)

Substitute \(x = 9\) into \((8x + 7)\):
\(m\angle B=8\times9+7\)
\(m\angle B=72 + 7=79\).

Answer:

\(79\)