X Y

-2 5

-1 3

0 1

1 - 1

2 - 3

Find the explicit formula and the type of function

Just by looking at it, we can see that y decreases by 2 for every x value, so it's

a (a can be any real number) - 2x (it's - 2 multiplied by x because it decreases by 2). Plugging it in for 0, we get a-2*0=1, and a=1, making the explicit function

y=-2x+1. Since a linear equation is in the form y=mx+b (with m and b both representing any number), this fits the description.