Answer:
-20
Explanation:
Unfortunately, there is no shortcut to solve these... you have to do the work, iteration by iteration.
A recursive function is a function that calls itself and takes as input the output of the previous call.
a = -2 a + 4
a1: 1
a2: -2 (1) + 4 = -2 + 4 = 2
a3: -2 (2) + 4 = -4 + 4 = 0
a4: -2 (0) + 4 = -0 + 4 = 4
a5: -2 (4) + 4 = -8 + 4 = -4
a6: -2 (-4) + 4 = 8 + 4 = 12
a7: -2 (12) + 4 = -24 + 4 = -20
so a7 = -20