5to the power of 7 divided by 5 times 5 to the power of 3

What is r i 4.5+10r=-6.5 with work pls

What is the point slope form of a line with slope -5 that contains point (2,-1)

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.