Answer: 
Step-by-step explanation:

Answer:
D
Step-by-step explanation:
To obtain f(g(x)) substitute x = g(x) into f(x), that is
f(10 - 5x)
= (10 - 5x)² + 5 ← expand (10 - 5x)²
= 100 - 50x - 50x + 25x² + 5 ← collect like terms
= 25x² - 100x + 105 → D
Identify the steps that complete the proof.
♣ = <span>✔ vertical angles theorem</span>
♦ = <span>✔ SAS</span>
♠ = <span><span>✔ CPCTC</span></span>