 Solve for a Variable in a Formula

In these lessons, we will learn how to solve a formula for a variable. It is also called solving literal equations.

Solving for a variable in a formula involves similar steps to solving for a variable in an equation. Let us review the steps as follows when we need to solve for a variable in a formula. Example:

The formula for the area of a circle is A = pr2 . Solve for r in the formula .  Example:

The formula for the area of a circle is A = pr2 . Solve for r in the formula .  How to solve a formula with variables for a specified variable?
Examples:
1. Solve for r
d = rt

2. Solve for h
A = 1/2 bh

3. Solve for b2
A = 1/2(b1 + b2)

4. Solve for w
P = 2L + 2W

5. Write y in terms of x
y - 3 = 1/3(x - 4)

6. Solve for a
1/a + 1/b = 1/2

Solving formulas for given variables
Examples:
1. c = ipv, solve for v
2. p = a + 3b + 2c, solve for a
t = 3j + 3v, solve for k
Solving an Equation for a Specified Variable
Examples:
1. Solve for Solve for b1
A = 1/2h(b1 + b2)

2. Solve for z
3z + x - y = 2x + 4

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