Step-by-step explanation:
x+y=4
y= [tex]x^2-3x+4[/tex]
Substitute the given value of y into the x+y=4 equation:
x+x^2-3x+4=4
Rearrange:
-2x+[tex]x^2[/tex]=0 ---> [tex]x^2=2x[/tex]
Try and solve for the rest of x on your own. Then substitute in and solve for y.
I hope this helps. If it did, please mark me as Brainliest. Good luck!