Question

I need help i have no idea how to do this

Answer 1

Prove 1

`\begin{gathered} AB=3y-1 \\ BC=7y \\ AC=29 \\ AB+BC=AC \\ 3y-1+7y=29 \\ 3y+7y=29+1\text{ (after collecting like terms)} \\ 10y=30 \\ y=(30)/(10) \\ \\ y=3 \\ AB=3y-1 \\ \text{then} \\ AB=3(3)-1 \\ AB=9-1 \\ \text{Therefore } \\ AB=8 \end{gathered}`

Prove 2

`\begin{gathered} AB=AC-BC_{} \\ AB=29-7y \\ We\text{ have found y as 3} \\ AB=29-7(3) \\ AB=29-21 \\ AB=8 \end{gathered}`