Hey there!
First, divide both sides by 12
-12(k+4)/-12= 60/-12 and you would getk+4=5
Now subtract 4 from both sides
k+4-4= 5-4
k=-9
Answer:

Step-by-step explanation:
Total number of toll-free area codes = 6
A complete number will be of the form:
800-abc-defg
Where abcdefg can be any 7 numbers from 0 to 9. This holds true for all the 6 area codes.
Finding the possible toll free numbers for one area code and multiplying that by 6 will give use the total number of toll free numbers for all 6 area codes.
Considering: 800-abc-defg
The first number "a" can take any digit from 0 to 9. So there are 10 possibilities for this place. Similarly, the second number can take any digit from 0 to 9, so there are 10 possibilities for this place as well and same goes for all the 7 numbers.
Since, there are 10 possibilities for each of the 7 places, according to the fundamental principle of counting, the total possible toll free numbers for one area code would be:
Possible toll free numbers for 1 area code = 10 x 10 x 10 x 10 x 10 x 10 x 10 = 
Since, there are 6 toll-free are codes in total, the total number of toll-free numbers for all 6 area codes = 
D. {x | x E R} because its all real numbers
Answer:
1. 4/5
2. 80%
Step-by-step explanation:
<u><em>Answer:</em></u>
You should multiply the expression by 
<u><em>Explanation:</em></u>
To rationalize any expression, you must multiply it by its conjugate. A conjugate is defined as a similar expression to the original one but with an opposite sign
<u>This means that:</u>
The conjugate of a + b would be a - b
Now, the given expression is 
<u>Consider the denominator:</u>
From the above, we can conclude that the conjugate of
is 
<u>And, remember that</u> we need to keep the value of the expression unchanged. This means that we must multiply both the numerator and the denominator by the same value
<u>Therefore:</u>
You should multiply the expression by
in order to rationalize the denominator
Hope this helps :)