Algebra I in Simple English/Working with Numbers/Formulas

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Contents 1 Vocabulary 2 Lesson 3 Example Problems 4 Practice Games 5 Practice Problems

[edit] Vocabulary

[edit] Lesson

In this lesson we will be learning formulas. A formula is a standard procedure for solving a class of mathematical problems

There are many diffrent kinds of formulas and like it or not most of us high school kids need to know some of them.

To give you an example of a formula we will show you the formula for finding area.

To find the area of a square you multiply the length times the width. If this square is five inches wide and five inches long you would multipy five times five and get twenty five, that would be the area of this square

  ...........
  .         .
  .         .      
  .         .
  .         .      bh(base x hight) is the actuall formula that should be given. 99% sure.
  ...........      -Luke

  So that is the formula for area:Length times width oF course there are other harder formulas you will have to work with but now you know the basics of what a formula is.

A formula is an established form of words or symbols for use in a ceremony or procedure

Formula for volume of a sphere: Vsphere=πr³

A diameter stretches from one side of the circle to the other, passing through the center.

The radius of a circle goes from the center to the outside of the circle.

Area of a Square: area = width x height

[edit] Example Problems

Example A:

Solve for 'y':

(a = 7)

a +5 + y = 20

Answer:

a + 5 + y = 20 (Put the 7 in place of the 'a')

7 + 5 + y = 20 (Add the integers, add 7+5=12)

12 + y = 20

12-12 + y = 20 - 12 (to get the 12 to the other side, add -12 to each side.)

                             (20-12=8)

y = 8 (this leaves y=8)

Check:

a + 5 + y = 20 (to check it, put the 7 in place of the a, and the 8 in place of

                              the y.  7+5+8=20)

7 + 5 + 8 = 20

Example B:

Solve for 'x':

(a = 7)

5 + 2 + x + a = 24

Answer:

5 + 2 + x + 7 = 24

14 + x = 24

14-14 + x = 24-14

x = 10

Check: 5 + 2 + x + a = 24

5 + 2 + 10 + 7 = 24

[edit] Practice Games

put links here to games that reinforce these skills

[edit] Practice Problems

(Note: put answer in parentheses after each problem you write)