Question

2 find the value of x.
a x = 22
b x = 90
c x = 9
d x = 68

Explanation:

Step1: Use the triangle angle - sum property

The sum of angles in a triangle is \(180^{\circ}\). Given a right - triangle (one angle is \(90^{\circ}\)), we have the equation \((3x - 5)+(7x + 5)+90=180\).

Step2: Simplify the left - hand side of the equation

Combine like terms: \((3x+7x)+(- 5 + 5)+90=180\), which simplifies to \(10x+90 = 180\).

Step3: Solve for \(x\)

Subtract \(90\) from both sides: \(10x=180 - 90\), so \(10x=90\). Then divide both sides by \(10\): \(x=\frac{90}{10}\).

Answer:

\(x = 9\) (Option C)