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1. ax+z=aw-y, for a

2. -14n+q= rt-4n, for n

 Oct 28, 2014

Best Answer 

 #5
avatar+130466 
+5

3. P=(1.2w)/h^2, find h.

Multiply both sides by h^2

h^2*P = 1.2w

Divide both sides by P

h^2 = (1.2w)/P

Take the positive root of both sides...since h is a positive quantity

h =√[1.2w/P]

4. 9/10g=7+2/3k, find k

Multiply both sides by the LCM of 3 and 10, i.e., 30

27g = 210 + 20k

Subtract 210 from both sides

27g - 210 = 20k

Divide both sides by 20

[27g - 210 ]/ 20 = g

5. 2-3/4p=5/6r+5, find r.

Multiply through by the LCM of 4 and 6, i.e., 12

24 - 9p = 10r + 60   

Subtract 60 from both sides

24 - 9p - 60 = 10r

Divide both sides by 10

[24 - 9p - 60 ] / 10  = r

 

Notice that the trick of multiplying through by the LCM first allows us to get rid of those nasty fractions in our work !!!

 

 Oct 28, 2014
 #1
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And to add to that sorry. 

3. P=(1.2w)/h^2, find h.

4. 9/10g=7+2/3k, find k

5. 2-3/4p=5/6r+5, find r. 

 

THANKS!

 Oct 28, 2014
 #2
avatar+23254 
+5

1)  Get all the terms that contain an 'a' to the left side; get all the other terms to the right side:

          ax + z  =  aw - y           (Subtract aw from both sides.)

          ax - aw + z =  -y           (Subtract z from both sides.)

          ax - aw  =  -y - z           (Factor a out of the left side.)

          a(x - w)  =  -y - z          (Divide both sides by x - w.)

          a  =  (-y - z) / (x - w)

2)  Get all the terms that contain an 'n' to the lift side; get all the other terms to the right side:

          -14n + q  =  rt - 4n          (Add 4n to both sides.)

          -14n + 4n + q  =  rt         (Subtract q from both sides.)

          -10n  =  rt - q                  (Divide both sides by -10.)

               n  =  (rt - q) / -10

               n  =  (q - rt) / 10

 Oct 28, 2014
 #3
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0

Can you also answer the other part that I posted?

 Oct 28, 2014
 #4
avatar+23254 
+5

P = (1.2w) / h²                 (Cross-multiply:)

Ph²  =  1.2w                     (Divide by P:)

h²  =  1.2w/ P                   (Find the square root:)

h  =  ±√(1.2w/P)

(9/10)g =  7 + (2/3)k                   (Subtract 7:)

(9/10)g - 7  =  (2/3)k                   (Multiply by 3/2:)

(3/2)[( 9/10)g - 7 ]  =  k               (Distribute:)

(27/20)g - 21/2  =  k

2 - (3/4)p  =  (5/6)r + 5        (Subtract 5:)

-3 - (3/4)p  =  (5/6)r            (Multiply by 6/5:)

(6/5)[ -3 - (3/4)p ]  =  r        (Distribute:)

-18/5 - (9/10)p  =  r

 Oct 28, 2014
 #5
avatar+130466 
+5
Best Answer

3. P=(1.2w)/h^2, find h.

Multiply both sides by h^2

h^2*P = 1.2w

Divide both sides by P

h^2 = (1.2w)/P

Take the positive root of both sides...since h is a positive quantity

h =√[1.2w/P]

4. 9/10g=7+2/3k, find k

Multiply both sides by the LCM of 3 and 10, i.e., 30

27g = 210 + 20k

Subtract 210 from both sides

27g - 210 = 20k

Divide both sides by 20

[27g - 210 ]/ 20 = g

5. 2-3/4p=5/6r+5, find r.

Multiply through by the LCM of 4 and 6, i.e., 12

24 - 9p = 10r + 60   

Subtract 60 from both sides

24 - 9p - 60 = 10r

Divide both sides by 10

[24 - 9p - 60 ] / 10  = r

 

Notice that the trick of multiplying through by the LCM first allows us to get rid of those nasty fractions in our work !!!

 

CPhill Oct 28, 2014

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