Lesson 1.4 Objectives: To solve a formula for one of its variables To Rewrite an equation in function form Vocabulary Literal Equations: Are equations and formulas involving several variables We have seen many literal equations Samples: D = RTA = BH I = PRT Y = 3X + 5V = LWH P = 2L + 2W Essential Question: How do I solve an equation that has more than one variable.

Solving for indicated variable means to isolate the indicated variable by using the correct steps. D = RT Solve for T Isolate the T D = RT Divide both sides by R R DRDR = T A = LW ex Solve for L Isolate the L A = LW Divide by W W AWAW = L

Vocabulary Function Form: A two variable function in which the output (range y) is isolated on one side of the equal sign. Ex: Y = 3x + 5 Rewrite in function form. Solve for Y 1. 3x + y = 7Subtract 3x from both sides –3x –3x Y = 7 – 3xorY = –3x + 7

2. 2y + 6x = 10Subtract 6x from both sides –6x –6x 2y = 10 – 6x Divide everything by y = 5 –3x or y = –3x x – y = 12 Subtract 3x from both sides –3x –y = 12 – 3x We need to solve y not –y So divide everything by -1 –1 –1 –1 y = –12 + 3x or y = 3x – 12

EX: A = S 2 The opposite of squaring a number is finding its square root. The exponent and square root cancel Solve for S EX:P = 2L + 2W solve for L -2W P – 2W = 2L Subtract 2W Divide both sides by 2 2 2