SOLUTION: Solve the following: 1.P = 2l + 2w, for l 2.C = 5/9(F - 32), for F

Algebra ->  Finance -> SOLUTION: Solve the following: 1.P = 2l + 2w, for l 2.C = 5/9(F - 32), for F       Log On


   

Question 1189079: Solve the following:
1.P = 2l + 2w, for l
2.C = 5/9(F - 32), for F

Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!



This is basic algebra, so I stongly encourage you to practice this until you know it cold.  Otherwise it will hinder you during your learning of more advanced topics.



1.  Solve P = 2l + 2w,  for l



Step-by-step...

    Subtract 2w from both sides (performing valid operation on both sides does not change the equality):

     P - 2w = 2l + 2w - 2w

    

    Simplify:

     P - 2w = 2l



    Divide both sides by 2:

     (P - 2w)/2 = 2l/2



    Simplify:

     (P - 2w)/2 = l  



    Re-write with l on left hand side:

      +highlight%28+l+=+%28P-2w%29%2F2%29+



When you have mastered this, you will do most of the above steps in your head.



2.   C = (5/9)(F - 32)



    i) Multiply both sides by (9/5)  & simplify

      (9/5)C =  (5/9)(F - 32)*(9/5)   

       // On right hand side, notice (5/9)*(9/5) = 1

      (9/5)C =  F - 32



    ii) Add 32 to both sides  & simplify

       (9/5)C + 32 = F - 32 + 32

       (9/5)C + 32 = F



        +highlight%28+F+=+%289%2F5%29C+%2B+32%29+



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When you hear "move the 2 to the other side"  it really means "do the opposite operation to both sides of the equation"

 

For example:  Solve for x:  y = 2x + 12



"move the 12 to the other side" means to subtract 12 from both sides (the subtraction "undoes" the addition on the right):  y - 12 = 2x + 12 -12



y - 12 = 2x   (one normally doesn't first write  2x + 12 - 12)



"move the 2 to the left hand side"  here means divide both sides by 2:

 (y - 12)/2 = x  



Now we re-write with x on the left hand side:

  x = (y - 12)/2