Answer:
x = 21
Step-by-step explanation:
If RECT is a rectangle, each of its interior angles are right angles, 90°. Since ∠RTC is split into two angles, the sum of the two angles must be 90°. (Angles that add to 90° are called complementary angles).
∠RTC = ∠RTE + ∠ETC Formula for complementary angles
90 = 2x + 6 + 42 Substitute the angles
90 = 2x + 48 Combined like terms to simplify
Now isolate "x" to solve
90 - 48 = 2x + 48 - 48 Subtract 48 from both sides
42 = 2x
42/2 = 2x/2 Divide both sides by 2
x = 21
Therefore x is 21.
