Escribe una expresión lineal con variable x, que valga 0 cuando x = 7 y
valga 12 cuando x = 10.

Will mark 50 show all what is the solution to the system of equations? use the substitution method and show your work. -5x+y= -3 -15 x+3y=7 explain what your answer in part (a) tells you about the association of the lines in this system.