## Solving Systems of Linear Equations with Row Reduction on the TI-83 Plus and TI-84 Plus

Suppose you wanted to find the solutions to the following set of equations:

Xavier and Yolanda both bake pies. In one hour, the pair create a total of 5 pies. If Xavier works for 3 hours and Yolanda works for 4 hours, the pair can create a total of 17 pies. How many pies does each produce per hour?

This tutorial discusses how to solve such problems, and a clever trick to make even the hardest linear simultaneous equations easy.

## Welcome Back!

We hope you’ve had a great summer! Calcblog is back, and we have some exciting new articles planned. We’re starting with an article on solving systems of linear equations scheduled for next week, and after that will be providing more test prep articles as the standardized testing season rolls around. As always, we love hearing from our users on what kinds of articles they want to see on our site. Let us know via our contact page. We look forward to hearing from you.

Cheers, and happy learning!

## Matrices Made Easy: TI-83 and TI-84 Plus Edition

Performing any type of mathematical operation such as addition or multiplication that involves matrices can be a daunting task, especially if you have to do all the steps without the aid of a calculator. Fortunately, your graphing calculator can solve your matrix math problems in seconds, whether you are adding or multiplying matrices or just trying to solve the inverse of a matrix. Keep reading to learn how to work with matrices on your TI-83 or TI-84 graphing calculator.

## Changing the Number of Decimals Displayed on the TI BA II Plus and HP 12c

Depending on the problem you are solving or your preferences, you may want to change the number of decimal places that are displayed on your financial calculator. Fortunately, this is quite easy to do. Keep reading to learn how to change the way numbers and decimals are displayed on the TI BA II Plus and HP 12c financial calculators. This tutorial also discusses comma versus decimal notation on the HP 12c.

Filed under Difficulty: Easy, HP 12c, TI BA II Plus | 2 Comments

## Settings on the TI-83 Plus and TI-84 Plus: The MODE Menu

The TI-83 Plus and TI-84 Plus offer a variety of different settings for customizing calculations and the way graphs are displayed. While some of these options are more aesthetic, like setting the graph to be displayed in a split screen or numbers to be displayed with two decimals for doing calculations with money, not having some settings configured correctly can lead to making errors in your calculations. This tutorial explains the various display mode settings available on the TI-83 Plus and TI-84 Plus, which can be reached by pressing .

Settings Menus on the TI-83 Plus and TI-84 Plus, respectively

Filed under Difficulty: Easy, TI-83 Plus, TI-84 Plus | 5 Comments

## SAT Test Prep #3: Calculating Sale Prices, Percentages and Discounts

One of the ways you can improve your SAT is score is identifying problems that may seem simple but are actually written to trick you. If you are rushing through a test, you may miss out on easy points. Consider the following, seemingly simple problem:

A dress is on sale at a clothing store. During the discount sale its price is reduced by 40%. Staff are allowed a further 30% reduction on the discounted price. If a staff member buys the dress for 42 dollars, what was the original price of the dress, in dollars?
(A) \$71.40
(B) \$76.44
(C) \$82.00
(D) \$88.25
(E) \$100.00

How do you find the price of the dress? Pick you answer and keep reading to find out how to solve the problem!

Filed under Algebra, Difficulty: Easy, SAT, Test Prep, TI-83 Plus, TI-84 Plus, TI-89 | 1 Comment

## Business and Finance Math #5: Calculating the Effective Annual Rate (EAR) on the TI-83 & TI-84 Plus

While they are intended primarily for math and statistics work, the TI 83 Plus and TI 84 Plus also have a slew of built in financial functions similar to those available on advanced financial calculators. This tutorial describes how to use the EAR (effective annual rate) and NOM (nominal rate) functions of your calculator to solve the problems in Financial Math Tutorials 2 and 3, which covered conversion between effective annual rates and stated interest rates.

## Business and Finance Math #4: Continuous Compounding on the TI BA II Plus & HP 12c

Sometimes when reviewing time value of money (TVM) problems, you may encounter a situation that involves continuous compounding. As we have seen in our previous posts on interest rates and calculating effective rates, the more times compounding occurs, the higher the effective rate, and the more you will earn on your investment or bank account (or pay on a loan). This naturally leads to the question: what is the maximum benefit you can receive from compounding? Enter continuous compounding, where compounding occurs constantly. As soon as interest is earned on an investment, it is immediately compounded. Keep reading to learn how to solve problems with continuous compounding on your TI BA II Plus or HP 12c financial calculator.

Filed under Difficulty: Easy, Finance, HP 12c, TI BA II Plus | 3 Comments

## How to Graph Equations on the TI-83 Plus and TI-84 Plus

Calcblog’s very first video walks you through all the powerful graphing features available on your TI-83 Plus and TI-84 Plus. Keep reading to learn how to graph functions, find values at specific points along an equation, and use some of your calculator’s more advanced features such as finding the value at the intersection of two functions.

Filed under Difficulty: Easy, TI-83 Plus, TI-84 Plus | 2 Comments

## How to Change the Batteries on Your TI-83 Plus, TI-84 Plus or TI-89

At some point while using your graphing calculator, you will turn on your calculator and be greeted with one of the following messages:

Unlike in many portable electronics, changing your calculator’s batteries does not simply mean swapping them out. In this article, learn about the different batteries in your calculator and how to change them without losing your calculator’s data.

Filed under Difficulty: Easy, TI-83 Plus, TI-84 Plus, TI-89, Voyage 200 | 20 Comments