Download presentation

Presentation is loading. Please wait.

Published byNatalie Gibbs Modified over 5 years ago

1
Copyright © 2013, 2009, 2005 Pearson Education, Inc. Section 1.4 Variables, Equations, and Formulas

2
Copyright © 2013, 2009, 2005 Pearson Education, Inc. Objectives Basic Concepts Modeling Data Square Roots and Cube Roots

3
Copyright © 2013, 2009, 2005 Pearson Education, Inc. Basic Concepts A variable is a symbol, such as x, y, or t, used to represent any unknown number or quantity. An algebraic expression can consist of numbers, variables, arithmetic symbols (+,,, ), exponents, and grouping symbols, such as parentheses, brackets, and square roots. Examples:

4
Copyright © 2013, 2009, 2005 Pearson Education, Inc. Basic Concepts An equation is a statement that two algebraic expressions are equal. Examples: A formula is an equation that can calculate one quantity by using a known value of another quantity.

5
Copyright © 2013, 2009, 2005 Pearson Education, Inc. Example If a car travels at a constant speed of 65 miles per hour, write a formula that calculates the distance d that the car travels in t hours. Evaluate your formula when t = 2.5 and interpret the result. Solution The car will travel a distance of 65 miles in one hour. Evaluating for t = 2.5 After 2.5 hours the car has traveled 162.5 miles.

6
Copyright © 2013, 2009, 2005 Pearson Education, Inc. Example Write a formula that does the following. a. Finds area of a circle with radius r. b. Calculates the pay P for working H hours at $12 per hour c. Converts Q quarts to G gallons Solution a. The area of a circle is A = r 2, where = 3.14. b. P = 12H c. There are 4 quarts in a gallon, so G = 4Q.

7
Copyright © 2013, 2009, 2005 Pearson Education, Inc. Example Evaluate each formula for the given value(s) of the variable(s). a. A = r 2, r = 5 b. P = 2L + 2W, L = 12 and W = 6 Solution a.b.

8
Copyright © 2013, 2009, 2005 Pearson Education, Inc. Example The data in the table can be modeled by the formula y = ax. Find a. xy 14 28 312 416 520 Solution Each value of y is 4 times the corresponding value of x, so a = 4.

9
Copyright © 2013, 2009, 2005 Pearson Education, Inc. Square Roots The number b is a square root of a number a if b 2 = a. For example, one square root of 16 is 4 because 4 2 = 16. The other square root of 16 is 4 because ( 4) 2 = 16.

10
Copyright © 2013, 2009, 2005 Pearson Education, Inc. Example Evaluate each expression. a.b. c.

11
Copyright © 2013, 2009, 2005 Pearson Education, Inc. Example Find the length of a side s for each geometric shape. a. A square with area 144 square feet b. A cube with volume 512 cubic inches Solution a. Squareb. Cube

Similar presentations

© 2019 SlidePlayer.com Inc.

All rights reserved.

To make this website work, we log user data and share it with processors. To use this website, you must agree to our Privacy Policy, including cookie policy.

Ads by Google