What is the sequence 12 21 30 39

How does difference of squares work?

5:4 clown fish to angel fish ratio of angel fish to gold fish 4:3. There is 60 clown fish. How many angel fish are there? How many goldfish are there?

For what values of $x$ is it true that $x^2 - 5x - 4 / le 10$? Express your answer in interval notation.

Explain in your own words, what are reciprocals and when are they used?

A rectangular prism has a length of 2 y, a width of 3 y, and a height of 5 y. If the volume of the prism is 10,290 units, what is the value of y?

Round 9947 to the nearest hundred

In △DEF, d = 20, e = 25, and f = 30. Find m∠F to the nearest degree.

so far this week emma has read more then 3 times as much as he read last week. he read 360 pages this week how many pages could he have read last week

The cost (in dollars) of making n birthday cakes is represented by C=24n+35. How many birthday cakes are made when the cost is $395? explain your reasoning

Paige has 24 magazine's in her magazine collection each month she adds 2 more megazines to her collection how many magazines will she have in 3 months write two number sentences to show how to solve