Be sure to fully show the system of equations for each problem and the process used to solve the system.You are starting an office-cleaning service. You decide to charge both large and small offices. You charge $55 for a small office and $85 for a large office. You clean 14 offices and make $920. How many small offices and how many large offices did you clean?

Respuesta :

Given:

The charge for a small office = $55.

The charge for a large office = $ 85.

The total number of offices = 14.

The total amount = $ 920.

Required:

We need to find a number of small offices and large offices.

Explanation:

Let x be the number of the small office and y be the number of the large office.

The equation of the total number of offices.

[tex]x+y=14[/tex]

[tex]x=14-y[/tex]

The equation of the total amount.

[tex]55x+85y=920[/tex]

Substitute x =14-y in the equation.

[tex]55(14-y)+85y=920[/tex]

[tex]55\times14-55y+85y=920[/tex]

[tex]770+30y=920[/tex]

Subtract 770 from both sides of the equation.

[tex]770+30y-770=920-770[/tex][tex]30y=150[/tex]

Divide both sides by 30.

[tex]\frac{30y}{30}=\frac{150}{30}[/tex][tex]y=5[/tex][tex]Substitute\text{ y=5 in the equation x=14-y.}[/tex][tex]x=14-5[/tex][tex]x=9[/tex]

Final answer:

The equations are

[tex]x+y=14[/tex]

[tex]55x+85y=920[/tex]

The number of small offices are 9.

The number of large offices are 5.