complex numbers-solving equations

i don't know how to put these equations into perfect squares so i can get the complex number to put on the Argand diagram(Doh)

(^ means 'to the power of' because i don't know how to use small letters)

1. 2x^(2)-7x+9=0

2. z^(3)-3z^(2)+z+5=0

and theres something else in the text book that doesnt make sense to me.

it says....

Determine the values of x and y by equating real and imaginary parts

1. x+3i=2-iy

2. 3x+i(y+1)=6+3i

can someone please try to solve these step by step so i know how you did them.... thanks!(Yes)