Posted by layth on .
if x.y=30 and x+y=10.3, what is x?
i been told by my teacher to use quadratic formula , and him and i did it , we end up having , x1=5.155.89i and x2=5.15+5.89i, y1=30/(5.155.89i) and y2=30/(5.15+5.89i).and he told to go from there, but i cant get final answe. as you know i=square root of 1. but i can solve this
(5.155.89i)times 30/(5.155.89i) ???

algebra 
Anonymous,
xy=30 and x+y = 10.3
that means y = 10.3x from equation two now put that into equation one
x(10.3x)=30
x210.3x+30 do the quadratic thing now