Question

what is the value of a?
write your answer as an integer or as a decimal rounded to the nearest tenth.
a =
submit

Explanation:

Step1: Apply exterior angle theorem

The exterior angle of a triangle equals the sum of the two non-adjacent interior angles, so:
$$5a = 42 + (2a + 4)$$

Step2: Simplify the right-hand side

Combine like terms on the right:
$$5a = 2a + 46$$

Step3: Isolate the variable term

Subtract $2a$ from both sides:
$$5a - 2a = 46$$
$$3a = 46$$

Step4: Solve for $a$

Divide both sides by 3:
$$a = \frac{46}{3} \approx 15.3$$

Answer:

$a \approx 15.3$