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 (2,64)
y = 4 × 4 x

Question 2:

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

Question 3:

A is (0,5) and
B is (1,25)
y = 5 × 5 x

Question 4:

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

Question 5:

A is (2,-12) and
B is (4,-48)
y = -3 × 2 x

Question 6:

A is (1,-10) and
B is (3,-40)
y = -5 × 2 x