x2+(7-x)2=25
-x2+7x-10=0
2x-3=1-2x+x2
2x2–7x+3=0
7x2+21x-28=0
x2–4x+4=0
x2–2x+1=0
x2+x+1=0
-x2+4x-7=0
x2–5x+6=0
x=2
x= ∉ℝ
x1=5, x2=2
x1=1, x2=-4
x=∉ℝ
x1=3, x2=2
x1=3, x2=1/2
x=1
x1=4, x2=3