Answer:
12.6
Step-by-step explanation:
If 21 divided by 5 is 4.2, you should multiply 3 by 4.2 you'll then get 12.6. to double check, do 5 divided by 3, which is 1.67, and 21 divided by 12.6 is also 1.67. so side OP is 12.6! :)
D = \/(0-(-2))² + (-6-4)²
d = \/(0+2)² + (-10)²
d = \/(2² + 100)
d = \/(4+100)
d = \/104
d ~ 10,20
All it takes for a relation to be a function is for each possible first number of a pair there's only one possible second number.
So if any of the sets has two pairs with the same first number, that one's not a function.
The last one has (3,2) and (3,5) so isn't a function.
