A initial investment of $10,000 grows at 18% per year. What function represents the value of the investment after t years?

∠AEB = 70°

Explanation:
1- solving for x:
When two lines intersect, the vertically opposite angles formed would be equal.
In the given, we have two intersecting lines, therefore:
∠AEB = ∠CED (vertically opposite angles)
2x + 50 = 7x
7x - 2x = 50
5x = 50
x = 50/5
x = 10

2- getting the measure of the angle:
We know that:
∠AEB = 2x + 50
x = 10
Therefore:
∠ AEB = 2(10) + 50
∠AEB = 20 + 50 = 70°

Hope this helps :)