An archaelogist in Turkey discovers a spear head that contains 23% of its original amount of C-14. Find the spear head to the nearest year. pls help

What are the sotions to the quadratic equation 9x^2=4

What is the range of the function? f(x)=-2|x+1|? a. all real numbers. b. all real numbers less than or equal to 0. c. all real numbers less than or equal to 1. d. all real numbers greater than or equal to 1

What is the value of x in the equation 1/5x - 2/3y = 30 , when y = 15