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Let me introduce you to Simple. Simple has often been accused of being simple minded but he is not! Simple does like things to be easy.

The quadratic formula can have more than one right answer. It also has more than one way of getting the solution. In the GED math class I use only one method and let the student find other solution methods to the one I teach. Simple likes the fact he only needs to remember one formula or equation.

a+ bx + c = 0 is the quadratic formula

2+ 4x -30 = 0 is a valid quadratic formula whose answer is -5 or 3.

Values in the formula are:

• a = 2

• b = 4

• c = -30

Simple's General solution equation:

x = (-b ± sqrt ( - 4ac )) ÷ 2a

x1 = (-4 - sqrt ( 16 + 240 )) ÷ 4 = (-4 -16) ÷ 4 = -20 ÷ 4 = -5

x2 = (-4 + sqrt ( 16 + 240 )) ÷ 4 = (-4 + 16) ÷ 4 = 12 ÷ 4 = 3

x1 and x2 are the 2 possible answers. Remember the rule for signs.? In x1 I subtracted from the -b. In x2 I added to the -b. Use a calculator if you have one for the square roots.

A mnemonic I use is: Minus b plus or minus the square root of b squared minus four ac divided by two a.

Sometimes Simple likes to sing with his scratchy voice which irritates me. I need to tell him to stop but he loves to sing so.

Simple's mnemonic songs.

You can sing along too (to the tune of Jingle Bells) even Pop Goes the Weasel:

X equals (jingle bells)
Negative b (jingle bells)
Plus or minus radical (jingle all the way)
B-squared minus four a c (oh what fun it is to ride)
All over two (in a one-horse open)
A! (sleigh!)

If you sing above twice you will hate me but never forget the solution formula. I point out that math may use mnemonics even songs. The visuals are a good way to remember math steps. Write them twice correctly to fix them in your memory.

For some people x1 and x2 is where they trip up.

+ 1x -4 = 0 has an answer of -4 or 1.

See if that is what you get!