Answer:
I'm not 100% sure I'm right but I think x = -1
because it says "f(x)" and then it says"Find f(-1)" so that is why I think x = -1
Answer:
Option C
Step-by-step explanation:
you cancel the whole parentheses.
So you know, x+6 can't equal to 0.
that's why there is a choice that is all real numbers but not -6.
Answer:

Step-by-step explanation:

Hope this helps!
You have in the first equation "+y" and in the second "-y"
So, you add the 2 equations, so we can remove this 2 letters since they're opposite numbers.
So, we get:
-4x + y -5x - y = 21 + 6
-4x -5x = 21 + 6
Then, you add
-4x -5x = 21 + 6
-9x = 27
Then, you move the -9 to the other part, next to the 27. And since it was a multiplication, it becomes a division.
x =


Then, you choose an equation of the system, and you replace x by it's value so you can find y. I'll take the first equation.
-4x + y = 6
-4*-3 + y = 6
12 + y = 6
Then, you move 12 to the other part next to the 6. And since it was a positive number, it becomes a negative number.
So
y = 6 - 12
y = -6
So, the solution of the proposed system <span>is (x;y) = (6;-6)
x = 6
y = -6
Hope this Helps :)
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