Answer:
Write the formula for one measurement, then solve the formula for the different measurement you want to find and use this new formula to find that measurement.
Step-by-step explanation:
We can understand this through an example.
If we need to find the lenght of a rectangle whose width is 4 feet and whose perimeter is 28 feet, we can use a formula for one measurement to write a formula for a different measurement:
- We need to write the formula for the perimeter of a rectangle:
[tex]P=2l+2w[/tex]
Where "l" is the lenght and "w" is the width.
- Since we know the width and the perimeter of the rectangle and we need to find the lenght, we can solve for "l":
[tex]P=2l+2w\\\\P-2w=2l\\\\l=\frac{P-2w}{2}[/tex]
Now we get a new formula for calculate a differente measurement (the lenght of the rectangle).
- Substituting values, we get:
[tex]l=\frac{28ft-2(4ft)}{2}=10\ ft[/tex]
