11 is the answer.
10+10=20
20-9=11
11+9=20
11
<u><em>Answer:</em></u>5n-4
<u><em>Explanation:</em></u><u>The given expression is:</u>

<u>1- Take the negative as a common factor from both the numerator and the denominator. This will give us:</u>

<u>2- Cancel out the negative sign (common factor) from the numerator and denominator. This will give us:</u>

<u>3- Factor the numerator. This wil give:</u>

<u>4- Finally, cancel out the (17n+19) which common in both numerator and denominator. This will give us the final expression:</u>
5n-4
Hope this helps :)
Answer:
0.15
Step-by-step explanation:
42 ÷ 63
63 -> 420
63x6=378
420-378=42
63->420
So, how many times does 63 go into 42? Well, it doesn't. So put down a zero on your paper, and then a decimal. So if we add a zero onto 42, it becomes 420. Well, 420 is divisible by 63. In fact, 63 goes into 420 6 times, making a total of 378. 420-378 = 42. Then the process begins again. So you've got a 0.6, and that six just keeps on repeating. On paper, you're gonna wanna put a dash over the six to show that it's repeating.
Anyways, the answer is .66 repeating.
A = 5 km is your distance it is how far he traveled.
b = 3 km is your displacement it's the length in which he when north.