Why does: 5x+3x+2x = 10x and not 10xxx?

The cost of using a service is $0.25 per min. what equation correctly represents the total cost c, in dollars, for d days of use?

Which of the following statements is true? a. the irrational number system is not closed under multiplication, because the product of two irrational numbers is always a rational number. b. the irrational number system is not closed under multiplication, because the product of two irrational numbers is not always an irrational number. c. the irrational number system is closed under multiplication, because the product of two irrational numbers is always an irrational number. d. the irrational number system is closed under multiplication, because the product of two irrational numbers is always a rational numbers. reset submit

The function below is written in vertex form or intercept form. rewrite them in standard form and show your work. y = (x+4)(x+3)