Question

Find the values of x and y, x and y are real numbers

5+(x+2y)i=x+3i

Answer 1

\(5+xi+2yi=x+3i\)
you need the i terms do match and the non i terms to match

so

x+2y=3
and
x=5

so

5+2y=3 gives
y=-1, x=5

Answer 2

note \(5+xi+2yi=5+(x+2y)i\)