Literal Equations Notes Algebra 1

1. LITERAL
EQUATIONS
Section 2.8 pages 126-131

2. Literal Equation
An equation involving several variables.
Also known as a formula.
𝐶 = 2𝜋𝑟

3. Solve 𝐶 = 2𝜋𝑟 for the radius 𝑟.
𝐶 = 2𝜋𝑟
𝐶
2𝜋
=
2𝜋𝑟
2𝜋
𝐶
2𝜋
= 𝑟

4. Find the radius of the world’s largest yo-yo
given that the circumference is 32.7 feet.
𝐶 = 2𝜋𝑟
𝐶
2𝜋
= 𝑟
From the information above we know 𝐶 = 32.7
32.7
2𝜋
= 𝑟
5.2 ≈ 𝑟
The radius is
Approximately
5.2 feet.

5. Solve 4𝑥 − 3𝑦 = 8 for 𝑥. Isolate the 𝑥.
4𝑥 − 3𝑦 = 8
+3𝑦 + 3𝑦
4𝑥 = 8 + 3𝑦
4𝑥
4
=
8 + 3𝑦
4
𝑥 =
8
4
+
3𝑦
4
𝑥 = 2 +
3
4
𝑦

6. Solve 3𝑥 − 2𝑦 = 𝑥𝑧 + 5 for 𝑥.
−𝑥𝑧−𝑥𝑧
+2𝑦 +2𝑦
3𝑥 − 𝑥𝑧 = 5 + 2𝑦
Opposite of
Distributive
Property
𝑥(3 − 𝑧) = 5 + 2𝑦
3𝑥 = 𝑥𝑧 + 5 + 2𝑦
𝑥 (3 − 𝑧)
(3 − 𝑧)
=
5 + 2𝑦
(3 − 𝑧)
𝑥 =
5 + 2𝑦
3 − 𝑧

7. Given the equation 𝑥 = 𝑏 − 𝑐𝑑 solve for 𝑐.
𝑥 = 𝑏 − 𝑐𝑑
−𝑏−𝑏
−𝑏 + 𝑥 = −𝑐𝑑−𝑏 + 𝑥
−𝑑
−𝑐𝑑
−𝑑
−𝑏 + 𝑥
−𝑑
= 𝑐

9. Homework
■ Literal Equations Worksheet
■ Chapter 2 Review