Answer:
Step-by-step explanation:
69, 70, 71, and 72
69 and 71 are the first and third digits. 69+71=140
In this problem the big angle will be equal to two times the smaller angle so the correct expression is:

Now we can rewrite the equation so:
Answer:
Can't really expand x and 0, so I guess it would just be x * 0
Step-by-step explanation:
explained above :)