Question

solving for interior angle measures
what is the m∠acb?
○ 10°
○ 50°
○ 90°
○ 180°
(7x - 20)°
(4x)°
(right angle at a)

Explanation:

Step1: Sum angles of right triangle

$90^\circ + (7x-20)^\circ + (4x)^\circ = 180^\circ$

Step2: Simplify the equation

$90 - 20 + 7x + 4x = 180$
$70 + 11x = 180$

Step3: Solve for $x$

$11x = 180 - 70$
$11x = 110$
$x = 10$

Step4: Calculate $m\angle ACB$

Substitute $x=10$ into $(7x-20)^\circ$:
$7(10) - 20 = 70 - 20 = 50$

Answer:

50° (Option: 50°)