For what value(s) of x is the expression undefined?

Idon’t understand this.. will someone ? will mark brainliest along with 20 points.

What is not true about kl and mn? what is mn? (show )

Asunflower was 20 1/2 inches tall. over the next 6 months, it grew to a height of 37 inches tall. what was the average yearly growth rate of the height of the plzzz write a proportion i will give you 100 points