BRAINLIEST! URGENT! Please help me, If you can explain how you got the answer and if you answer both questions, I will mark you Brainliest.

Answer:
1. I have simplified the first question:
[tex]x=\frac{10-ab}{a-4};\quad \:a\ne \:4[/tex]
2. I have found the parabola properties:
[tex]\left(h,\:k\right)=\left(\frac{5}{2},\:\frac{25}{4}\right),\:p=-\frac{1}{4}[/tex]