I need help solving this problem asap!!!! please

[firemansgurl]

Suppose that the length of a rectangle is three cm longer than twice the width and that the perimeter of the rectangle is 90 cm.

A.) Set up an equation fot the perimeter involving only m, the width of the rectangle.
answer________

B.) Solve this equation algebrically to find the length of the rectangle. Find the width as well.
answer: W_______, L________

show your work

 

[stapel]

Since you haven't been able to show any progress, I'll guess that you're asking for help getting started. :wink:

Suppose that the length of a rectangle is three cm longer than twice the width and that the perimeter of the rectangle is 90 cm.

i) Since the length is defined in terms of the width, pick a variable for the width. (Hint: They've given you this in (A).)

ii) Create an expression, in terms of the variable in (i), for "twice the width".

iii) Create an expression, in terms of (ii), for "three more than" "twice the width". This stands for your length.

iv) Find the formula for the perimeter P of a rectangle with length L and width w.

v) Plug the value from the exercise, the variable from (i), and the expression from (iii) into the formula for (iv).

vi) Solve the quadratic equation in (v) for the value(s) of the variable.

vii) Interpret the solution(s) in the context of the original exercise and (i).

viii) Back-solve, using (iii), for the other dimension.

If you get stuck, please reply showing how far you have gotten in working through the steps. Thank you!

 

[Denis]

show your work

 

[Mrspi]

show your work

Here's how it works here...

YOU show your work.

When we can see what you've done to try to solve the problem, we'll have a better idea of what kind of help you need.