Please help and hurry please Which could be the first step in solving the equation represented by the model below?

3 x tiles and 4 negative 1 tiles = 2 x tiles and 5 positive 1 tiles
Add 4 positive unit tiles to each side.
Remove 4 unit tiles from each side.
Add 6 positive unit tiles to each side.
Remove 6 unit tiles from each side.

With these 5 geometry questions! pls 1.)quadrilateral abcd is inscribed in this circle.what is the measure of ∠a ? enter your answer in the box.°2.)quadrilateral abcd is inscribed in a circle.what is the measure of angle a? enter your answer in the box.m∠a= 3.)quadrilateral abcd is inscribed in this circle.what is the measure of angle b? enter your answer in the box.m∠b= °4.)quadrilateral abcd is inscribed in this circle.what is the measure of angle a? enter your answer in the box.°5.) quadrilateral abcd is inscribed in this circle.what is the measure of angle c? enter your answer in the box.°