The equation for line G is given by 5y=-2x-205y=−2x−20. Suppose line G is parallel to line R, and line E is perpendicular to line G. Point (-10, 8) lies on both line R and line E. Choose the correct equation for R and E from the choices below. Line E: y=\frac{5}x+33y= x 5 +33 Line R: y=-\frac{2}{5}x+4y=− 5 2 x+4 Line E: y=\frac{5}{2}x+33y= 2 5 x+33 Line R: y=-\frac{2}x+4y=− x 2 +4 Line R: y=-\frac{5}{2}x+8y=− 2 5 x+8

Really need on these. i have no idea what to do

Ascientist wants to use a model to present the results of his detailed scientific investigation. why would a model be useful? a )because the model makes the concepts easier to understand b) because the model is easy to put together and to use c) because the model prevents other scientists from asking questions d) because the model requires the audience to pay full attention to it i don't know what to choose because between a and d a is much more likely than d because it only wants to get the attention of the audience. i'm confuse.

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).