Question 588234
A = P(1+r/n)^t

Set the total value of the loan equal to 350 x t to find the number of months when they become equal

20000(1+.046/12)^t = 350t

1.00383333^t = .0175t

Cannot be solved analytically, solve graphically

{{{ graph( 900, 900, -1, 900, -1, 15, .0175x, 1.00383333^x) }}}

t = 76.6