Answer:
Option C
Step-by-step explanation:
we have

step 1
Group terms that contain the same variable, and move the constant to the opposite side of the equation

step 2
Factor -6 leading coefficient'

step 3
Complete the square
Remember to balance the equation by adding the same constants to each side


step 4
Rewrite as perfect squares

simplify

We know that : Sum of Angles in a Triangle is equal to : 180°
⇒ In ΔRST, The Sum of Angles ∠R , ∠S , ∠T should be equal to 180°
⇒ m∠R + m∠S + m∠T = 180°
⇒ (2x + 10)° + (2x + 25)° + (x - 5)° = 180°
⇒ (2x + 2x + x) + (10° + 25° - 5°) = 180°
⇒ 5x + 30° = 180°
⇒ 5x = 180° - 30°
⇒ 5x = 150°
⇒ x = 30°
I believ it’s 6. I’m not sure
It would be 40,000 if you rounded up