# 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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