Please answer the following question but, before you do please tell me what do y1 and y2 represent. Also what do x1 and x2 represent and lastly what do the letters a,b,c, d represent. Now you can answer the question without copying someone else's work please.

5.1 Suppose that x1 and x2 are linearly independent and define y1 = ax1 + bx2 and 2 = cx1 + dx2. Show that y1 and y2 are linearly independent if and only if ad # bc