PLEASE HELP solve the equation by completing the square. round to the nearest tenth if necessary.

x^2 - 12x + 9 = 0

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

Answer this question only if you know the answer! 30 points and

Jenisey has $24 to spend on seven pencils. after buying them she had $10. how much did each pencil cost.?