Given:
In △ABC is a right angle triangle.
AC is 6 units longer than side BC.
[tex]Hypotenuse=2\sqrt{17}[/tex]
To find:
The length of AC.
Solution:
Let the length of BC be x.
So, Length of AC = x+6
According to the Pythagoras theorem, in a right angle triangle
[tex]Hypotenuse^2=Base^2+Perpendicualar^2[/tex]
△ABC is a right angle triangle and AC is hypotenuse, so
[tex](2\sqrt{17})^2=(x)^2+(x+6)^2[/tex]
[tex]68=x^2+x^2+12x+36[/tex] [tex][\because (a+b)^2=a^2+2ab+b^2][/tex]
Subtract 68 from both sides.
[tex]0=2x^2+12x+36-68[/tex]
[tex]0=2x^2+12x-32[/tex]
[tex]0=2(x^2+6x-16)[/tex]
Divide both sides by 2.
[tex]x^2+6x-16=0[/tex]
Splitting the middle term, we get
[tex]x^2+8x-2x-16=0[/tex]
[tex]x(x+8)-2(x+8)=0[/tex]
[tex](x+8)(x-2)=0[/tex]
[tex]x=-8,2[/tex]
Side cannot be negative, so x=2 only.
Now,
[tex]AC=x+6[/tex]
[tex]AC=2+6[/tex]
[tex]AC=8[/tex]
Therefore, the length of AC is 8 units.
