# Solve help

• Solve
• Input help

On this screen you can solve equations, inequalities, or systems. If you need to perform a different operation, press the button and select the appropriate operation.

## Why doesn’t Algebrator ask me what variable to solve for?

Make sure that you have actually entered an equation or inequality (it needs to contain either the =, <, >, ≤, or ≥). For example, x + y + 2 is not an equation; it is an expression. On the other hand, x + y + 2 = 0 is an equation that can be solved (for either one of the variables).

## Why doesn’t Algebrator provide the solution for my equation?

Make sure that you have actually entered an equation or inequality (it needs to contain either the =, <, >, ≤, or ≥). For example, x + y + 2 is not an equation; it is an expression. On the other hand, x + y + 2 = 0 is an equation that can be solved (for either one of the variables). In addition, in rare instances the equation may be too hard for Algebrator to solve. In those cases, please press the button and send us a feedback email (the screenshot of your problem will be automatically attached).

## How can I solve a system of equations or inequalities?

Use the , key to separate equations or inequalities from each other.

## Why is my keyboard missing the ± symbol?

The ‘plus/minus’ is not a symbol that you will ever need to enter. It means that there are two equations, one with a ‘+’ sign and another one with a ‘- ‘ sign. Algebrator will always explicitly write out both equations, so there is no need for a combined ± symbol.

## How do I enter a new equation to solve?

Press the button and then select ‘New’. Alternatively, if your problem is very short, just press the key several times.

## How do I enter an exponent?

Enter the base and then press the power key ^, key to enter the exponent. Once you are done entering it, press the key to return the cursor to the base.

## How do I enter a mixed number (e.g. 5 ½) ?

There is no special notation for mixed numbers. You need to enter them as a sum (e.g. 5+½). If the mixed number is negative, make sure to place it in parentheses, e.g. -(5+½).

## How do I enter a fraction?

Fractions can be entered in two different ways. If you haven't started entering it, your best option is to use the fraction template key ÷, and "fill in" the numerator and denominator. If you have already started the fraction (e.g. in a+b you want the variable 'b' to be the fraction's numerator), the easiest way to complete it is to use the fraction line symbol /. If your numerator or denominator is complex, we highly recommend using the fraction template.

## How do I divide?

First, press the F symbol to access the alternate keyboard. Then, press the division symbol key for division.

## How do I enter an expression under a root?

If you need a square root, press the square root key , and enter the expression. If you need higher order roots (cube, etc.) then use the key to reach the root index and edit it.

## How do I edit something in the middle of an expression without erasing everything?

Use the key to reach the desired edit point. Alternatively, it’s possible to press the edit point, although this may be a little tricky, depending on the size of your touchscreen.

More than 90% of the problems found in a typical algebra textbook can be entered via the keyboard layout displayed on the previous screen. If you need to enter a different variable, a function, or a special constant (such as π), press the A or F keys to access alternate keyboards. Once you press an alternate keyboard key, the keyboard reverts to the primary keyboard.

The key remembers the last used variable. This will speed up the problem entry since you don't have to repeatedly access the alternate keyboard layout for frequently used symbols.

The and keys allow you to move through the expression, one character at the time. For faster (but less precise movement) you can press the desired edit point. These keys are also used to 'exit' exponents, denominators, and parentheses.

Always be aware of your cursor location. For example, if you type in a^2 to enter the power a2, make sure to 'exit' the exponent before adding another term (e.g. a2+2a). The exponent is exited via the key. If you don't, then your expression will look like this: a2+2a.

When you press the ( key, both left and right parenthesis are created, and the cursor is placed inside them. Once you are finished typing the parenthesized expression, use the key to exit the parentheses. The same concept applies to the absolute value key.

In order to use the subscript key _, you already need to have the variable (without subscript) typed in. The same goes for the power key ^. In contrast, if you want an expression under the root, first press the root key , and then enter the expression.