Answer: 22 months
Explanation:
From the question, we are informed that Mildred has $800 in her savings account and adds $25 each month. The function f(x)=25x+800 represents Mildred's bank account.
To calculate the number of months for Mildred to have $1, 350 goes thus:
f(x) = 25x + 800
25x + 800 = 1350
25x = 1350 - 800
25x = 550
x = 550/25
x = 22
The answer is 22 months.