Answer:
Solution given:
equation is:
x²-40x+A=0
when A=200
equation becomes
x²-40x+200=0
Comparing above equation with ax²+bx+c=0 we get
a=1
b=-40
c=200
By using quadratic equation formula
x=[tex]\displaystyle \frac{-b±\sqrt{b²-4ac}}{2a}[/tex]
substituting value
x=[tex]\displaystyle \frac{-*-40±\sqrt{(-40)²-4*1*200}}{2*1}[/tex]
x=[tex]\displaystyle \frac{40±\sqrt{800}}{2}[/tex]
x=[tex]\displaystyle \frac{40±20\sqrt{2}}{2}[/tex]
taking positive
x=[tex]\displaystyle \frac{40+20\sqrt{2}}{2}[/tex]
x=34.14
taking negative
x=[tex]\displaystyle \frac{40-20\sqrt{2}}{2}[/tex]
x=5.86
x=34.14 or 5.86
