will name the brainliest

Answer:
x = 622 (rounded to the nearest whole number value)
Step-by-step explanation:
=> Step 1: Solve for the base of top triangle;
Tan(39) = [tex]\frac{base1}{521}[/tex]
Tan(39) * 521 = base1
421.897 = base1
=> Step 2: Solve for the base of the bottom triangle;
Tan(21) = [tex]\frac{Base2}{521}[/tex]
Tan(21) * 521 = Base2
199.993 = Base2
=> Step 3: Finding x;
Base1 + Base2 = x
421.897 + 199.993 = x
621.89 or 622 = x
Hope this helps!