A man with $30 ,000 to invest decides to diversify his investments by placing $15,000 in an account that earns 6.2% compounded continuously and $15,000 in an account that earns 7.4% compounded annually. Use graphical approximation methods to determine how long it will take for his total investment in the two accounts to grow to $45,000.
We are looking for the intersection of
y = 45000 and
y = 15000 [ (1.074)^t + e^(.062t) ]
Here's a graph : https://www.desmos.com/calculator/zmejtzneea
The time is about 6 years....