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LESSON #7
Solving Literal Equations
A literal equation is an equation that uses more than one letter as a variable.
To Solve a formula for a variable:
(1)
isolate the variable on one side of the equal sign.
- use rules to solve equations
(2)
add, subtract, multiply, or divide both sides of the equation
to obtain a coefficient of 1 on the desired variable.
Example 1
Given P = 2 (L + W),
Solve for w.
Solution
a)
P = 2L + 2W
distribute
P - 2L = 2L - 2L + 2W
Subtract 2L
P - 2L = 2W
P - 2L = 2W
2
2
divide by 2
P - 2L = W
2
Example 2
5x – 2y – 11 = 0, y (put in y=mx + b form)
5x –2y + 2y – 11 = 0 + 2y
5x – 11 = 2y
5x – 11 = 2y
2 2
2
y = 5x – 11
2
2
SOLVE EACH EQUATION FOR THE DESIRED VARIABLE:
1.
A = bh + z , h
2.
g = m + x(w – 1) , w
3. C =d,
d