Solving Literal Equations Solving Literal Equations

When solving for a variable, you must When solving for a variable, you must isolateisolate the variable. the variable.

Think about opposites, how do you undo Think about opposites, how do you undo addition? Subtraction? Multiplication? addition? Subtraction? Multiplication?

Division?Division?

Isolating the VariableIsolating the Variable

1.1. Take care of all the addition and Take care of all the addition and subtraction signs first.subtraction signs first.

2.2. Then remove all of the division or Then remove all of the division or multiplication pieces.multiplication pieces.

Example 1: Example 1: y = mx + b, Solve for m. y = mx + b, Solve for m. y = y = m m x + bx + b• y – b = m x + b - b• y – b = m x x x• m = y - b x

Subtract b from both sides.

Divide by x on both sides.

Solve for m.

Example 2: Example 2: V = lwh, Solve for h. V = lwh, Solve for h.

V = lwhV = lwhDivide by lw on both sides.

• V = lwh lw lw

• h = V lw

Make sure h is by itself.

Example 3: Example 3: P = 2L + 2W, Solve for L. P = 2L + 2W, Solve for L.

P = 2L + 2wP = 2L + 2w Solve for L. Subtract 2w

from both sides.

• P -2w = 2L + 2w -2w

Divide by 2 on both sides.

• p – 2w = 2L 2 2 Make sure L

is by itself. •L = p-2w 2

Class work: Class work: You try these: You try these: 1.1. VVff = V = Vii + at, Solve for t. + at, Solve for t. 2.2. A = ½h (bA = ½h (b11 + b + b22), Solve for h.), Solve for h.3.3. F = 9/5 C + 32, Solve for C.F = 9/5 C + 32, Solve for C.

Summary: Summary: Why is it important to be able to Why is it important to be able to solve for a specific variable solve for a specific variable within a formula? within a formula?