For each of the problems, twice the angle formed by the chords is equal to half the sum of the angles of the arcs.
So, for the first problem, we have

, so

.
For the second,

, so

.
For the last problem,

, so

.
Feel free to comment below if you have any questions!
Answer: it's 6x + 8 if you solve it
Step-by-step explanation:
To find a rat of change (ROC) you take the two numbers and the two prices and subtract them to make a ratio<u>:</u>
<u>_</u><u>_</u><u>_</u><u>_</u><u>6</u><u>-</u><u>3</u><u>_</u><u>_</u><u>_</u><u>_</u><u>_</u> = <u>_</u><u>_</u><u>_</u><u>3</u><u>_</u><u>_</u><u>_</u>
$2.56-$2.44 = $2.12
The reduce to the lowest number (the 3 to a 1)
<u>_</u><u>_</u><u>3</u><u>_</u><u>_</u><u>_</u> = <u>_</u><u>_</u><u>_</u><u>1</u><u>_</u><u>_</u>
$2.12 $0.71
The ROC is $0.71
ANSWER
B. The two middle coefficients add to the correct number but do not multiply to the correct number.
EXPLANATION
The given quadratic trinomial that Tina tries to factor is

Comparing to

we have a=10, b=-13 and c=-3
ac=-3×10=-30
We split the middle term so that their sum is -13.
Tina use
-10,-3
to get
-10x-3x
The sum is -13x alright but the product is not -30.
B is correct.