I don't understand how to do these. With the last one, I graphed each function but they all looked symmetric. Please help and show how to solve these. Thanks!

Guest Oct 23, 2019

#1**+1 **

The first one is a little tricky, but not that hard if we just think about it

The total perimeter = 2 (70 + 50) = 2 * 120 = 240 m

The point (0, 0) is one point on the graph.....at 0 minutes we have walked 0 m !!!

Also.....if the person walks for three minutes......he has walked 3(80m) = 240 m = 1 round

So....he has made 1 round in 3 minutes

So....the point ( 3,1) should be on the graph

So.....the graph at the bottom left is the correct one

Note that after 6 minutes, we have made 2 rounds

So.....(6,2) is also on the graph

CPhill Oct 23, 2019

#2**+1 **

If the graph is symmetric with the y axis....it is an * even* function which means that

[Symmetric with y means that we can fold the graph over the the y axis and it will lay on top of itself ]

f(x) = f(-x)

Look at A

f(x) = 4 - x^2

f(-x) = 4 - (-x)^2 = 4 - x^2

Since f(x) = f(-x)......this is the one that is symmetric withthe y axis

See the graph here : https://www.desmos.com/calculator/trwnp3rhxf

CPhill Oct 23, 2019