To solve this you need to use the formula for Chord-Chord length. You need to know it, it is ab=cd. with this, we can plug numbers in. a=30 b=x+1 c=2x-6 d=21 So our new equation is: 30(x+1)=21(2x-6) 30x+30=42x-126 156=12x x=13 This isn't what the question is askign for though, it wants YZ Which is A+B or 30+x+1 or 21+13=34. YZ=34
