Urgent! cine se pricepe la matematică. [clasa a 8-a]
îmi poate explica și mie cineva funcțiile și expresiile? sau măcar una din ele. aș fi recunoscătoare dacă m-ați ajuta.

Acable company wants to provide cell phone service for residents on an island. the function for the cost of laying the cable from the island to the mainland is c(x)= 6.500 square root x2+4, where x represents the length of the cable in feet. what are the domain and range of the function? a) domain: all real numbers range: all real numbers greater than or equal to 17,000 b) domain: all real numbers greater than or equal to 0 range: all real numbers greater than or equal to 17,000 c) domain: all real numbers greater than or equal to 0 range: all real numbers greater than or equal to 13,000 d) domain: all real numbers greater than or equal to 13,000 range: all real numbers greater than or equal to 0

Write numerical coefficient of y² in the expression 2x² - 15xy – 7y²

Sara made $253 for 11 hours of work. at the same rate how much would he make for 7 hours of work?