Answer:
Part (A): The required equation will be:
![6d+20b=150](https://img.qammunity.org/2020/formulas/mathematics/high-school/m98cdhnp1jo89rwj8htv51mlei94vhifl0.png)
Part (B):The required equation will be:
![d=(150-20b)/(6)](https://img.qammunity.org/2020/formulas/mathematics/high-school/byirp7v5necheu1h4uqq61qy9b8lqnfdks.png)
Part (C):The required equation will be:
![b=(150-6d)/(20)](https://img.qammunity.org/2020/formulas/mathematics/high-school/fzjkmj9wkvivuu4v5urv4muwmqjexhzmk2.png)
Explanation:
Consider the provided information.
Let d represents number of packages of hot dogs and b represents the number of packages of hamburgers.
Part (a)
It is given that the cost of a package of hot dogs is $6 and cost of a package of hamburger is $20.
The required equation will be:
![6d+20b=150](https://img.qammunity.org/2020/formulas/mathematics/high-school/m98cdhnp1jo89rwj8htv51mlei94vhifl0.png)
Part (b) Solve the above equation for d.
Subtract 20b from both sides.
![6d=150-20b](https://img.qammunity.org/2020/formulas/mathematics/high-school/ypvwe1cjil6cscpa396v5uo3lkj68bdl80.png)
Divide 6 from both sides.
![d=(150-20b)/(6)](https://img.qammunity.org/2020/formulas/mathematics/high-school/byirp7v5necheu1h4uqq61qy9b8lqnfdks.png)
The required equation will be:
![d=(150-20b)/(6)](https://img.qammunity.org/2020/formulas/mathematics/high-school/byirp7v5necheu1h4uqq61qy9b8lqnfdks.png)
Part (c) Solve the equation for b.
Subtract 6d from both sides.
![20b=150-6d](https://img.qammunity.org/2020/formulas/mathematics/high-school/nu9hpme91b9lhctrya2ng13phlyl47qux6.png)
Divide 20 from both sides, we get
![b=(150-6d)/(20)](https://img.qammunity.org/2020/formulas/mathematics/high-school/fzjkmj9wkvivuu4v5urv4muwmqjexhzmk2.png)
The required equation will be:
![b=(150-6d)/(20)](https://img.qammunity.org/2020/formulas/mathematics/high-school/fzjkmj9wkvivuu4v5urv4muwmqjexhzmk2.png)