Question

 

Solve. 

A.  c = 10d + 5n for n 

B.  L = 2rh for r 

Answer 1

Solve for a specific variable :

Some equations such as the one above contain more than one variable.At times, we will need to solve these equations for one of the variable.

• A.

The equation is c = 10d + 5n.

Apply subtraction property of equality : Subtract 5n from each side.

c - 5n = 10d + 5n - 5n

Apply additive inverse property : a - a = 0.

c - 5n = 10d

Apply subtraction property of equality : Subtract c from each side.

c - 5n - c = 10d - c

Apply additive inverse property : a - a = 0.

- 5n = 10d - c

Apply division propert of equality : Divide each side by negative 5.

(- 5n)/(- 5) = (10d - c)/(- 5)

Cancel common terms.

n = - (10d - c)/5

n = (c - 10d)/5.

The value of n = (c - 10d)/5.

• B.

The equation is L = 2rh.

Apply division propert of equality : Divide each side by  2.

L/2 = 2rh/2

Cancel common terms.

L/2 = rh

Apply division propert of equality : Divide each side by  h.

(L/2)/h = rh/h

Cancel common terms.

(L/2)/h = r

Multiply 2 and h in the denominator.

L/(2 * h) = r

L/2h = r.

The value of r = L/2h.