Question

sum of angle measures: 360°

Explanation:

Step1: Set up the equation

The sum of the interior angles of a quadrilateral is \(360^{\circ}\). So, \((x - 5)+(x + 35)+1.4x+x=360\).

Step2: Simplify the left - hand side of the equation

Combine like terms: \((x+x + 1.4x+x)+(-5 + 35)=360\).
\(4.4x+30 = 360\).

Step3: Solve for \(x\)

Subtract \(30\) from both sides: \(4.4x=360 - 30\).
\(4.4x=330\).
Divide both sides by \(4.4\): \(x=\frac{330}{4.4}=75\).

Answer:

\(x = 75\)