ANSWER
mFJH = 210º
Step-by-step explanation
The measure of an arc is twice the measure of the inscribed angle subteded by it:
![\text{mFJH}=2m\angle FGH](https://img.qammunity.org/2023/formulas/mathematics/college/87q8gc464tmwhqgecmg5ph3so9d88txk3u.png)
First we have to find x:
![17x-28=2(6x+21)](https://img.qammunity.org/2023/formulas/mathematics/college/hz11r60bs5emh87rlh8n3nj9i3ze80iz42.png)
Apply distributive property of addition on the right side:
![\begin{gathered} 17x-28=2\cdot6x+2\cdot21 \\ 17x-28=12x+42 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/mjdcbqv0q0fx3j9y44z3gthvds5rrkrkql.png)
Now we have to get the x together on the same side of the equation. To do that we have to subtract 12x from both sides:
![\begin{gathered} 17x-12x-28=12x-12x+42 \\ 5x-28=42 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/oorci0itdxlx9k1u30zv86f5xfcxg1oxz8.png)
Now, add 28 to both sides:
![\begin{gathered} 5x-28+28=42+28 \\ 5x=70 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/s7era2d7n42llwzhk6s5q7u8yppxufusg8.png)
And finally divide both sides by 5:
![\begin{gathered} (5x)/(5)=(70)/(5) \\ x=14 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/g467azdlsihgtta8eqeayento5ny0ch4qc.png)
Now, with x = 14, we just have to replace it into the expression for the measure of arc FJH:
![\begin{gathered} \text{mFJH}=17x-28 \\ \text{mFJH}=17\cdot14-28 \\ \text{mFJH}=238-28 \\ \text{mFJH}=210 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/q6w76b8xdoyf3heoze0spl8njlmpgfe86f.png)
The measure of arc FJH is 210º