Question

How many solutions does the system of equations Have? 6x+9y=7; y=-3/2x+4 I Need help with this two. Could any one explain it to me how to get the answers?

Answer 1

`6x + 9 = 7 \: and \: y = - (3)/(2)x + 4 \\ \\ means \\ \\ 6x + 9( ( - 3)/(2)x + 4) = 7 \: \: or \\ 6x - (27)/(2)x + 36 = 7 \: \: or \\ \\ (27)/(2)x - 6x = 36 - 7 \: and \\ \\ (27)/(2)x - (12)/(?2)x = 29 \\ \\ (15)/(2)x = 29 \\ x = (29)/(1) * (2)/(15) = (58)/(15) \\ \\ y = - (3)/(2) * (58)/(15) + 4 \\ = ( - 174)/(30) + (120)/(30) = - (54)/(30) = - (27)/(15)`