Download presentation

Published byAudrey McIntyre Modified over 4 years ago

1
**1.1 What you should learn Why you should learn it Variables in Algebra**

GOAL 1 Evaluate a variable expression. GOAL 2 Write a variable expression that models a real-life situation. Why you should learn it To express real-life number relationships.

2
**1.1 Variables in Algebra 1 GOAL EVALUATING VARIABLE EXPRESSIONS**

VOCABULARY variable values variable expression evaluating an expression

3
**To evaluate a variable expression, follow these three steps: **

Write the variable expression. Substitute values for variables. Simplify the numerical expression. EXAMPLE 1

4
Extra Example 1 Evaluate each expression when y = 3. Click for solutions. 1. 4y y y EXAMPLE 2

5
Extra Example 2 Find the average speed, of a car that traveled 89 miles in 2 hours. Solution: average speed 44.5 mi/h EXAMPLE 3

6
Extra Example 3 Find the perimeter, a + b + c, of the triangle. The dimensions are in centimeters. Click to see the solution. a = 1 b = 1.75 c = 2.25 Perimeter = a + b + c = = 5 cm

7
Checkpoint 1. Find the average speed of a car that travels 225 miles in 4.5 hours. 50 mi/h Find the perimeter of the triangle. The dimensions are in inches. Click for the answers. c = 6.7 a = 8 b = 8 EXAMPLE 4 22.7 in

8
**convert the interest rate**

Extra Example 4 Find the simple interest, Prt, you will earn in two years on a deposit of $870 at a rate of 5% per year. Click for the solution. Simple interest = Prt = Did you remember to convert the interest rate to a decimal number? These units cancel. $87

9
**1.1 Variables in Algebra 2 GOAL MODELING A REAL-LIFE SITUATION**

VOCABULARY Unit Analysis Verbal Model EXAMPLE 5

10
Extra Example 5 You plan to ride your bicycle to school and back at an average rate of 6 miles per hour for a distance of 10.5 miles. How long will it take you? Click to see the solution. VERBAL MODEL LABELS ALGEBRAIC MODEL Time = Time = t Distance = 10.5 miles Rate = 6 mi/h 1.75 hours

11
Checkpoint 1. Find the simple interest you will earn after one half of a year with a deposit of $1250 at a rate of 6% per year. $37.50 Your parents drive to the grocery store 9 miles away at 12:30 p.m. and return at 2:00 p.m. If the grocery shopping took 45 minutes, what was the average speed of their car? Click for the answers. 24 mi/h

12
QUESTIONS?

Similar presentations

OK

Preview Warm Up California Standards Lesson Presentation.

Preview Warm Up California Standards Lesson Presentation.

© 2018 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