Question

solve for x. 10° 18° 20° 22.5°

Explanation:

Step1: Identify angle - sum relationship

The two angles \(4x\) and \(5x\) are complementary (since the angle at \(A\) is a right - angle, \(90^{\circ}\)). So, \(4x + 5x=90^{\circ}\).

Step2: Combine like terms

Combining the left - hand side of the equation, we get \(9x = 90^{\circ}\).

Step3: Solve for \(x\)

Divide both sides of the equation \(9x = 90^{\circ}\) by 9. So, \(x=\frac{90^{\circ}}{9}=10^{\circ}\).

Answer:

\(10^{\circ}\)