What is the value of x in triangle 45 and 56

What are the constants in this expression? -10.6+9/10+2/5m-2.4n+3m

Reflect the point (7,0) across the y-axis

Hector and alex traded video games. alex gave hector one fourth of his video games in exchange for 6 video games. then he sold 3 video games and gave 2 video games to his brother. alex ended up with 16 video games. how many video games did alex have when he started?