Answer:
AC = 23 so it be D
Step-by-step explanation:
plug AC = DF ---> 21x-19 = 3x+17
sub. 3x by both sides --> 18x-19 = 17
add 19 to both sides --> 18x = 36
divide both sides by 18, x = 2
plug x back into 21x-19 to find AC
21(2) - 19
42 - 19 = 23
Keywords:
<em>Pair of numbers, negatives, law of signs, multiply
</em>
For this case we must say that it is obtained by multiplying any even number of negative numbers, that is, if a positive or negative number is obtained.
We must bear in mind that the Law of Signs states that:

For example:
Let -a, -b, -c, -d negative numbers, we have:
- A pair:

- Two pairs:

This is true for the multiplication of any pair of negative numbers.
So, the answer is: You get a positive number
Answer:
A positive number is obtained
Answer:
Solution is x = 8.
Step-by-step explanation:
2 is not a solution as √2*2 - 2 is not equal to -4.
0.9 is the answer to this simple question