Answer:
Each girl gets 2/3 yd of ribbon.
Step-by-step explanation:
12 2/3=38/3
(38/3)/19
(38/3)(1/19)
(2/3)(1/1)=2/3
It should be -48. Multiply 40 by the reciprocal and simplify.
Good question, I will find the answer and send it to you
Question 1:
For this case we have the following expression:
![\frac {\frac {y-1} {y ^ 2-36}} {\frac {1-7y} {y + 6}} =\\\frac {(7y-1) (y + 6)} {(y ^ 2-36) (1-7y)} =](https://tex.z-dn.net/?f=%5Cfrac%20%7B%5Cfrac%20%7By-1%7D%20%7By%20%5E%202-36%7D%7D%20%7B%5Cfrac%20%7B1-7y%7D%20%7By%20%2B%206%7D%7D%20%3D%5C%5C%5Cfrac%20%7B%287y-1%29%20%28y%20%2B%206%29%7D%20%7B%28y%20%5E%202-36%29%20%281-7y%29%7D%20%3D)
We have to:
![y ^ 2-36 = (y + 6) (y-6)](https://tex.z-dn.net/?f=y%20%5E%202-36%20%3D%20%28y%20%2B%206%29%20%28y-6%29)
Rewriting:
![\frac {(7y-1) (y + 6)} {(y + 6) (y-6) (1-7y)} =\\\frac {7y-1} {(y-6) (1-7y)} =](https://tex.z-dn.net/?f=%5Cfrac%20%7B%287y-1%29%20%28y%20%2B%206%29%7D%20%7B%28y%20%2B%206%29%20%28y-6%29%20%281-7y%29%7D%20%3D%5C%5C%5Cfrac%20%7B7y-1%7D%20%7B%28y-6%29%20%281-7y%29%7D%20%3D)
We take common factor "-" in the denominator:
![\frac {7y-1} {(y-6) * - (- 1 + 7y)} =\\\frac {7y-1} {- (y-6) * (7y-1)} =\\- \frac {1} {(y-6)}](https://tex.z-dn.net/?f=%5Cfrac%20%7B7y-1%7D%20%7B%28y-6%29%20%2A%20-%20%28-%201%20%2B%207y%29%7D%20%3D%5C%5C%5Cfrac%20%7B7y-1%7D%20%7B-%20%28y-6%29%20%2A%20%287y-1%29%7D%20%3D%5C%5C-%20%5Cfrac%20%7B1%7D%20%7B%28y-6%29%7D)
ANswer:
![- \frac {1} {(y-6)}](https://tex.z-dn.net/?f=-%20%5Cfrac%20%7B1%7D%20%7B%28y-6%29%7D)
Question 2:
For this case we must simplify the following expression:
![(3n ^ 4 + 1) + (- 8n ^ 4 + 3) - (- 8n ^ 4 + 2) =](https://tex.z-dn.net/?f=%283n%20%5E%204%20%2B%201%29%20%2B%20%28-%208n%20%5E%204%20%2B%203%29%20-%20%28-%208n%20%5E%204%20%2B%202%29%20%3D)
We eliminate parentheses keeping in mind that:
![+ * - = -\\- * - = +\\3n ^ 4 + 1-8n ^ 4 + 3 + 8n ^ 4-2 =](https://tex.z-dn.net/?f=%2B%20%2A%20-%20%3D%20-%5C%5C-%20%2A%20-%20%3D%20%2B%5C%5C3n%20%5E%204%20%2B%201-8n%20%5E%204%20%2B%203%20%2B%208n%20%5E%204-2%20%3D)
We add similar terms:
![3n ^ 4-8n ^ 4 + 8n ^ 4 + 1 + 3-2 =\\3n ^ 4 + 2](https://tex.z-dn.net/?f=3n%20%5E%204-8n%20%5E%204%20%2B%208n%20%5E%204%20%2B%201%20%2B%203-2%20%3D%5C%5C3n%20%5E%204%20%2B%202)
Answer:
![3n ^ 4 + 2](https://tex.z-dn.net/?f=3n%20%5E%204%20%2B%202)