Equations

3t = 18 is an equation. It is a mathematical sentence. It means that what is on the left side of  = is equal to what is on the right and that t (an unknown number) is multiplied by 3. To determine what t equals we use an elementary school procedure.   
4(5) = 20  To prove this is the correct answer we divide  20 ÷ 4 = 5     or   20 ÷ 5 = 4  

Any time you multiply 2 numbers together the answer divided by one of the numbers must produce the other number.  If not then you have multiplied incorrectly.

In our equation 3t = 18    3 and t are numbers that are being multiplied together. Therefore t = 18 ÷ 3 Hence t = 6
    So try this example:
 45632r = 593216   answer 

Another elementary school procedure involves addition and subtraction. 7 + 4 = 11 To prove the answer is correct we subtract one of the numbers from 11.  7 = 11 - 4  or  4 = 11 - 7  If 11 - 4 = 7 or 11 - 7 = 4   Then our answer is correct.

In algebra we can use the same concept to solve an equation.      R + 5 = 14  Therefore   R = 14 - 5   R = 9
Try this example  T + 346245 =  6478329   answer

A subtraction example:  7 - 4 = 3 To prove this answer correct we add 4 to 3   7 = 4+ 3 and if 4 + 3 equals 7 our answer 3 is correct. 

In algebra we can use the same concept to solve an equation. R - 4 = 6   therefore R = 6 + 4 and   hence  R = 10  
Try this example  P - 564783 = 432657       answer

Lets combine both procedures into one example:    4t + 7 = 39   4t is a number and we are adding 7 to it.
Therefore 4t = 39 - 7 →   4t = 32  and t = 32 ÷ 4 = 8  Therefore t = 8
Try this example:     37r + 16 = 275       answer

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