Which set is a function?

Which linear equations have an infinite number of solutions? check all that apply.  (x  –  3/7)  =  2/7(3/2x  –  9/14)8(x  +  2)  =  5x  –  1412.3x  –  18  =  3(–6  +  4.1x)(6x  +  10)  =  7(x  –  2)4.2x  –  3.5  =  2.1 (5x  +  8)

Answer question above and explain each step : )

Find the distance of the blue line between the two labeled points. round to the nearest hundredth. a) 7.07 b) 7.21 c) 10 d) 5.12