Problem 7 is choice B, which is the entire number line shaded in but the value -4 has a hole at this location to mean "exclude this point from the solution set". So basically x can be any number but -4.
Problem 8 is choice C. You have a closed circle (or filled in hole) at -1.5 on the number line. Then you shade to the left of the closed circle to indicate the set of values that are smaller than this endpoint. So n can be -1.5 or it can be smaller than -1.5 (something like -2 or -3, etc).
f(x)=x-4f(3)=3-4so f(3)= -1
Answer:
a system of linear equations with solution (x, y) = (1, -1)
Step-by-step explanation:
The two given linear equations in x and y are consistent and independent, so will have one solution. That solution is easily found using a graphing calculator. It is (x, y) = (1, -1).
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"What is ..." is a pretty open question with lots of different answers that won't be helpful. If you're seeking a specific answer, it would be nice to see the question say what answer you seek.
<span>Which of the following was a result of prison reform during the 1800s
A. a decrease in prisons
</span>
Suppose the equation went like this
-12 -24= x
You would essentially just add them together and put a negative sign in front of it so the answer would be -36. But once you start dealing with parentheses and brackets it get more complicated than that. Comment if you have any more questions :)