30. A box weighing 30 kilograms contains several student math books and one teacher's edition.
If each student book weighs 2.3 kilograms, the
teacher's edition weighs 4.3 kilograms, and the
box weighs 0.4 kilograms when empty, how
many student books are in the box?
A. 7
B. 11
C. 15
D. 23

What are the domain and range of the functiony = 2(x - 3)2 + 4?

Asegment in the complex plane has a midpoint at 7 – 2i. if the segment has an endpoint at 11 – 3i, what is the other endpoint?

Lance lived in portugal and brazil for a total of 14 months to learn portuguese. he learned an average of 130 new words per month when he lived in portugal, and an average of 150 new words per month when he lived in brazil. in total he learned 1920 new words. write a system of equations to represent the situation. use x to represent portugal, and y to represent brazil