An equation is a number sentence that represents two equal quantities . An equation can use numbers and letters called variables.

                                                                                               

1 + 6 = 7   (true equation)                            

Y – 4 = 10 ( open equation)

12 + 4 = 21 (false equation)

 

A function is a statement where one specific input, X , is matched with one specific output, Y. The results can form a pattern. Think of this like a machine where you take one quantity, perform a math operation, and get another quantity.

For example:

X + 4 = Y

 

X	Y
2	6
3	7
4	8

                                                                                                                     

 

Can you figure out the equation?

X	Y
2	4
4	8
6	12
8	16
10	20

 

References:

image of scale from tulanelink.com

image of grinder from mincer.en.alibaba.com