Answer: 75
Step-by-step explanation:
To find the value of 6c-15, we first want to finc the value of c. Once we find c, we can plug it in and solve.
-5c+6=-69 [subtract both sides by 6]
-5c=-75 [divide both sides by -5]
c=15
Now that we have the value of c, we can plug it in and solve.
6(15)-15 [multiply]
90-15 [subtract]
75
The value is 75.
To answer the question, let B call the amount of meat and P the number of potatoes.
The recipe says that for every pound of meat we need 3 potatoes.
Then that relationship is written as follows:


If we increase the amounts of the recipe by 100%, it will multiply by 2 the amount of meat and also that of potatoes. Therefore we need 2 pounds of meat and 6 potatoes.
Then the relationship is:

But 
Therefore, the proportion that represents the situation remains the same 
This occurs because the increase in the amount of potatoes and beef was in the same proportion.
Future help- Use the law of sines and law of cosines to solve triangles.
Answer- D= 26° b= 5.48 d=2.57