-4x + 3(2x - 5) = 31 (use distributive property to remove parentheses)
-4x + 6x - 15 = 31 (combine like terms)
2x - 15 = 31 (add 15 to both sides)
+15 +15
2x = 46 (divide both sides by 2)
x = 23
16 and 12 because 16-12=4 and 16+12=28
Answer: First option.
Step-by-step explanation:
You can use the inverse tangent function to find the value of the angle T:

You can identify in the figure that:

Then, knowing these values, you can substitute them into
.
Therefore, you get that the value of the angle T rounded to the nearest degree is:

This matches with the first option.
Answer:
4
Step-by-step explanation:
It becomes positive and stays positive
Answer:
mean= 90
Step-by-step explanation:
The mean is the terms added together, then divided by the number of terms (in this case, 8):

Done.