Answer:
a = 10/3.
Explanation:
We write the linear function as follows:
f(x) = mx + b where m is the slope and b is the y-intercept.
f(6) = 6m + b = 8
f(2) = 2m + b = 20 Subtracting these 2 equations:
4m = -12
m = -3.
and -3 * 2 + b = 20 so:
b = 20 + 6 = 26.
So we have the linear function:
f(x) = -3 x + 26
f(a) = 16 = -3 a + 26
-3 a = 16-26
a = -10 * -3 = 10/3.