Can someone show me how to do this ?

The point slope formula is y - y1 = m(x - x1)

the value x1 is the x coordinate of a point
the value y1 is the y coordinate of a point
the value m is the slope, which is 3

therefore, x1 = -2 & y1 = 1

Then, all you do is plug in the points:

y - 1 = 3(x + 2)

NOTE: It is 3(x + 2) instead of 3(x - 2) because the formula is (x - x1). If you plug x1 in, it is (x - (-2)). 2 negatives cancel out to be a positive, so it is (x + 2)