The date of the first sighting of robins has been occurring earlier each spring over the past 25 years at a certain laboratory. Scientists from this laboratory have developed two linear​ equations, shown​ below, that estimate the date of the first sighting of​ robins, where x is the year and y is the estimated number of days into the year when a robin can be expected. Complete parts a and b. ​(Hint: 2000 was a leap​ year.) y = 698−0.304x
y = 1539−0.736x

Solve this system of equations to find the year in which the two estimates agree.

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