Lesson 2 5 Literal Equations and Formulas September

Lesson 2 -5 Literal Equations and Formulas September 4, 2014

Daily Learning Target • I will rewrite and use literal equations and formulas.

Key Vocab. • Literal equation: an equation that involves two or more variables.

Solve It • You are ordering pizzas and sandwiches. You have a budget of $80. How many sandwiches can you buy if you buy 4 pizzas? What if you buy 5 pizzas? What if you buy 8 sandwiches?

Example 1 10 x + 5 y = 80 Solve for y Answer: y = 16 – 2 x

Example 2 •

Example 3 • What is the radius of a circle with a circumference of 64 ft? Round to the nearest tenth. Use 3. 14 for p. Use the appropriate formula: C = 2 pr Answer: r ≈ 10. 2 ft.

Example 4 • The monarch butterfly is the only butterfly that migrates annually north and south. The distance a particular group of monarch butterflies is 1700 from Indiana to Mexico. It takes a typical butterfly about 120 days to travel one way. What is the average rate at which a butterfly travels in miles per day? Round to the nearest mile per day. Answer: r ≈ 14 miles per day

Try It • This is what you will see on your homework 1) 3 x – 5 y = p; x = -1, 0, 1 2) mx + nx = p; Solve for x.

Homework • Workbook page 55 • Problems: 1, 3, 8, 10, 12, 16, 18 • Page 57 • Problems: 1 – 6 ALL