supply duct is to run the perimeter of a building having....

[daisyreyesr]

supply duct is to run the perimeter of a building having a length four times the width. The total duct length is 990 ft. What are the dimensions of the building?

Length: ft

Width: ft

A wire 60 cm long is to be cut into two pieces so that one piece is two times as long as the other. Find the length of each piece.

Short piece: cm

Long piece: cm

and hard one is 7x + 8y + 279=0
y=3x

 

[stapel]

supply duct is to run the perimeter of a building having a length four times the width. The total duct length is 990 ft. What are the dimensions of the building?

i) Pick a variable for the width.

ii) Create an expression, in terms of the variable in (i), for the length.

iii) Plug these, along with the given duct length, into the formula you've memorized for the perimeter of a rectangle.

iv) Solve for the variable.

v) Back-solve for the required values.

A wire 60 cm long is to be cut into two pieces so that one piece is two times as long as the other. Find the length of each piece.

There are three parts; one wire is one part, and the other is two parts. What is one-third of sixty? (Hint: Divide "60" by "3".) Then what is one part? What is two parts?

and hard one is 7x + 8y + 279=0
y=3x

Is this a system of equations? Are you supposed to solve using some particular method?

Please reply with a clear listing of your work and reasoning so far. Thank you!