How to solve/check equations

Today I will teach you how to solve/check equations.We will learn how to check first. Checking equations is way easier than solving them because the answer is already there. Just plug in your answer from the solve for the variable. But you still have to solve a problem. These are examples of checking equations.

Addition

x+5=12

7+5=12

12=12 (normally there would be a check mark above the equal sign)

x=7

Subtraction

7=y-5

7=12-5

7=7

y=12

Multiplication and division are a little bit more difficult.

Multiplication

3z=12 (3z is 3 times z)

3x4=12 (Instead of an "x" to multiply, a dot would be there)

12=12

z=4

Division

v divided by 3=4 (Normally a division problem would be written like a fraction)

12 divided by 3=4

4=4

v=3

It is very complex to do, so be very careful on how you do it. Now it is time to solve equations. Solving equations are very, very hard at first. Just do not confuse the solve with the check. This can cause you to get the wrong answer. Solving is just doing the opposite operation of a number. These are examples of solving problems.

Addition

x+10=17

-10 -10

x=7

Subtraction

y-12=5

+12 +12

y=17

Multiplication and division are hard to solve with. These are a couple of examples of those operations.

Multiplication

8v=16

divided by 8 8(supposed to be centered)

v=2

Division

v divided by 8x8= 2x8

v=16

(bold means work for this problem)


Hard at first, but a little bit easier along the way. This is very important to do later on. This is a few vocabulary words that are very important.



Variable-a random number, usually represented by a letter. x+5=9

Operation-addition, subtraction, multiplication, and division. +, -, x(this is a basic multiplication sign, but in problems it is written as a dot), (there is no division sign, but a basic division sign would be a minus sign with two dots above and below it. Normally written as a fraction.)

If you want to try it out yourself, click http://go.hrw.com/math/midma/gradecontent/loadlesson.html?course=c2&chapter=2&lesson=10&SE=1&sz_audio=1&calc=1&state=xx&actCourse=0 for the check and http://go.hrw.com/math/midma/gradecontent/loadlesson.html?course=c2&chapter=2&lesson=11&SE=1&sz_audio=1&calc=1&state=xx&actCourse=0 for the solve.That is the end of the lesson.