Exponential Functions: Find the equation through the points A and B in the form y = a b x

Question 1:

A is (0,-4) and
B is (1,-12)
y = -4 × 3 x

Question 2:

A is (0,-3) and
B is (2,-12)
y = -3 × 2 x

Question 3:

A is (0,-4) and
B is (1,-12)
y = -4 × 3 x

Question 4:

A is (3,-135) and
B is (4,-405)
y = -5 × 3 x

Question 5:

A is (3,24) and
B is (4,48)
y = 3 × 2 x

Question 6:

A is (2,27) and
B is (5,729)
y = 3 × 3 x