In a right angled triangle,
Hypotenuse2=base2+height2So,
AC2=AB2+BC2⇒(x+15)2=(x+8)2+(x+1)2⇒x2+225+30x=x2+64+16x+x2+1+2x ⇒225+30x=x2+65+18x⇒x2−160−12x=0⇒x2−20x+8x−(20×8)=0⇒x(x−20)+8(x−20)=0 ⇒(x−20)(x+8)=0⇒x=20 or x=−8
Since, length cannot be negative,
⇒x=20