## Pre-Algebra Calculator

[box title=”Study for Tests/Quizzes” color=”#003366″]The more you practice, the better prepared you’ll be. The calculator will give you extra problems to try. Look for the topic you wish to review in the Examples section of the calculator. A problem will show in the box. (If it’s hard to understand, that’s because it’s written in calculator notation. Click the Show button to view the problem in the standard mathematical format.)  Select Topic tells the calculator what to do with the problem; just make sure this matches the directions for the type of problem you want to practice.  Solve the problem and check your answer using the calculator. If you answer correctly, you’ll know you’re on the right track. If not, you’ll need to go back over your work to find your mistakes. If you can’t find it, ask a parent or friend for help or sign up for Mathway. Mathway will show you how to work the problem step-by-step so that you’ll be able to find your mistake and see how to solve the problem correctly.[/box]

1. You can enter the problem by using an example or by using the symbols.

2. Click the Show button next to Math Format. This will show your problem in the normal mathematical format that you’re used to. If it looks wrong and you need more help, click the ? Box next to the Enter Problem field.

3. The Select Topic dropdown will fill in with the most common type of problem, but if you want the calculator to do something different, just choose the correct option from the dropdown.

5. If you made a mistake, you need to figure out what you did wrong.  To see the steps, sign up for Mathway.

[note color=”#ffffd1″]Using an example:
Scroll through the topics to find the type of problems you want to check or practice. This will provide an example in the calculator so that you can see how it is formatted. You can then change the numbers or variables to fit the problem you are trying to check.[/note]

[frame align=”left”][/frame]Parenthesis – They indicate multiplication or that the operation inside should be done first.

[frame align=”left”][/frame]Brackets – Use brackets if you need a parenthesis within parenthesis – The brackets go on the outside as seen in this example: [3 + 2(10 -1)] ÷ 7.

[frame align=”left”][/frame]Absolute Value – The absolute value tells how far away a number is from zero. It’s always the same number but positive. For example,|3| is 3 and |-3| is also 3.

[frame align=”left”][/frame]Fractions – Type the numerator and denominator inside the parenthesis that will come up. To create a mixed number, delete the parenthesis and put a space between the whole number and the numerator of the fraction. For example, for 2¼ type 2 1/4.

[frame align=”left”][/frame]Exponents – Type the base before the ^ symbol and the exponent in parenthesis. For example, 5^(2) for 52. Remember that the exponent tells how many times the base is multiplied by itself.

[frame align=”left”][/frame]Square Roots – Type the radicand (the number inside the square root symbol) inside the parenthesis. Square roots find what number times itself equals the radicand. For example, the square root of 49 is 7 because 7 * 7 = 49.

[frame align=”left”][/frame]Other Roots – Type the index after the √ symbol and the radicand inside the parenthesis. For example, use √3:(8) for $\sqrt[3]{8}$. Remember that a different index means that the answer must be multiplied by itself that many times to equal the radicand. In our $\sqrt[3]{8}$ example, 2 * 2 * 2 = 8, so 2 would be the answer because 2 times itself 3 (the index) times is 8.
Note: If no index is given, it is assumed to be two and is just called a square root.

[frame align=”left”][/frame]Coordinates – Type a coordinate as you normally would – such as (1,5).

[frame align=”left”][/frame]Point/Slope – Use this button if you know one coordinate and the slope (m) of a line. You can then either find the equation of the line or see the graph of the line. Type the coordinate inside the parenthesis and the slope after the m= . For example, a line with slope of ½ and the coordinate (3,5) would look like this: (3,5),m=1/2.

[frame align=”left”][/frame]Scientific Notation – Inside the brackets, type the number then the exponent. For example, 2.6 x 10$^8$ would look like this: sci[2.6,8]. Remember that negative exponents are used for numbers less than zero.

[frame align=”left”][/frame]Greater Than or Equal To – If you need to use just the greater than sign ( > ), simply type it using your keyboard. (Hit shift then the period.)

[frame align=”left”][/frame]Less Than or Equal To – If you need to use just the less than sign ( < ), simply type it using your keyboard. (Hit shift then the comma.)

[frame align=”left”][/frame]Rectangle – In the brackets, type the length and width of the rectangle. The calculator can then give you the perimeter or area. Remember that perimeter is the distance around the outside of the figure (like a fence around a yard) and that area is the amount of surface the figure covers (like carpeting in a room.)

[frame align=”left”][/frame]Circle – Type the radius in the brackets. Radius is the distance from the center to the outside. If you’re given the diameter (the distance all the way across the circle), divide it by two to find the radius. The calculator can then produce the area or circumference of the circle. Circumference means the distance around the outside of the circle. The formula for the area of a circle is $A = \pi r$² and the circumference is $C = 2\pi r$.

[frame align=”left”][/frame]Triangle – Type the base and the height in the brackets. Remember that the height of a triangle makes a right angle with the base – it is not one of the sides unless you have a right triangle. The area of a triangle is found by using the formula A = ½bh.

[frame align=”left”][/frame]Parallelogram – A parallelogram has two pairs of parallel sides. Type the base and the height in the brackets. Remember that the height of the parallelogram makes a right angle with the base. The formula for the area of a parallelogram is A = bh.

[frame align=”left”][/frame]Trapezoid – A trapezoid has only one set of parallel sides. In the brackets, type one of the bases then the height then the other base. *Notice that the height must go in the middle. The bases are the two parallel sides of the trapezoid and the height makes a right angle with both bases. The formula for the area of a trapezoid is $A = \frac{1}{2}(b_{1}+b_{2})h$.

[frame align=”left”][/frame]Rectangular Prisms – Rectangular prism is the formal name for a box. Type the length, width, and height in the brackets. You can then find the volume or the surface area. Volume is the amount of space inside a figure (like the amount of water that will fit into a pool). Surface area is the area of all of the outside surfaces (like how much wrapping paper it would take to wrap the box).

[frame align=”left”][/frame]Cylinder – Type the height first then the radius. Remember that the radius is the distance from the center of the circle to the outside of the circle. The formula for the volume of a cylinder is $V = \pi r^{2}h$.

[frame align=”left”][/frame]Cone – Type the height first then the radius. Remember that the radius is the distance from the center of the circle to the outside of the circle. The formula for the volume of a cone is $V = \frac{1}{3} \pi r^2$.

[frame align=”left”][/frame]Rectangular pyramid – Type the height first then the length and width of the base. The formula for the volume of a rectangular pyramid is $V = \frac{1}{3} lwh$.

[frame align=”left”][/frame]Sphere – Type the radius of the sphere inside the brackets. Remember that the radius is the distance from the center of the sphere to the outside. If you are given the diameter (the distance all the way across), you must divide it by 2 to find the radius. The formula for the volume of a sphere is $V = \frac{4}{3} \pi r^2$. The surface area can be found using the formula $V = \frac{4}{3} \pi r^2$.

[frame align=”left”][/frame]Division sign – For multiplication, use the asterisk button on your keyboard. (Hit shift then 8).

[frame align=”left”][/frame]Pi – Pi is a unique number that describes the relationship between the circumference and the diameter of every circle. Pi is approximately equal to 3.14.

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• Pay attention in class. Listening and asking questions in class is really important. If you miss the instruction your teacher gives, you’ll have to figure it out on your own later. Not only will this take a lot more time, but it’ll also be more difficult to learn by yourself. So avoid the temptation to write notes to your friends or doodle during class and listen up! You’ll be glad you did.

• Take your homework seriously. Math homework is designed to give you a chance to practice what you learned in class. Your tests and quizzes will contain problems very similar to the ones on your homework, so if you know how to do your homework, you’ll know how to work them on the test. However, if you don’t know how to do the homework, you’re going to be in trouble. So do your very best. If you run into problems you can’t figure out, ask someone for help or write down a question to ask the teacher when you go over the homework in class the next day.

• Learn from your mistakes. You are going to make mistakes in math – it’s part of the process. What’s important is that you learn from your mistakes so that you don’t keep making them over and over. Whenever you get a problem wrong, you need to go back and figure out where you messed up. If you can’t find your error, ask a friend, parent, or teacher for help. Or, if your parents sign you up for Mathway, you’ll be able to see the steps for each problem and can find your error from there.

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