Because the image of the straight line and the straight line y=-2x+2 intersect at the same point on the y axis.

When x is 0, y is equal to.

So b=2.

Because the straight line y=kx+b passes through (2, -3),

So 2k+2=-3

So k=-2.5

So the analytical formula is y=-2.5+2.

2. because y=kx+b passes through (1, 2) and (-3, 4),

So the system of equations k+b=2.

-3k+b=4

The solution is k=-0.5 and b=2.5.

So y=-0.5x+2.5.