To calculate: 5 - 2[f(-1)]
We need to calculate first f(-1), so we need to replace x by -1 in the equation of f(x) as:
f(x) = -8x + 20
f(-1) = -8*(-1) + 20
f(-1) = 8 + 20
f(-1) = 28
Now, we can replace f(-1) by 38 and solve as:
5 - 2[f(-1)]
5 - 2*28
5 - 56
- 51
Answer: -51