Trufant is yoleni's older brother. the sum of their ages is 47. the difference of their ages is 9. how old are trufant and yosleni?

The factorization of 8x3 -125 is (2x-5)(jx2 +kx+25)

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

Varies inversely with x. if y=8.5 when x=-1 find x when y=-1