Answer:
115°
Step-by-step explanation:
In this case, we have two angles defined by an expression. It's important to know that m∠AEB and m∠DEC are congruent, because they are opposite by the vertex angles, which are always equal. So, we only have to equalize these angles each other.
[tex](5x-10)\°=(3x+40)\°\\5x-3x=40+10\\2x=50\\x=\frac{50}{2} =25[/tex]
Now, we replace this value in whatever expression, because they are the same.
[tex]5x-10=5(25)-10=125-10=115[/tex]
Therefore, the angle is 115°
