A= 1
B= -5
C= 10
In order to figure it out, you can think about it like this..
90 tens hopefully this helped
The 5x and the combination of (40° + x) are "vertical angles".
Vertical angles are equal.
So
5x = 40° + x
Subtract 'x' from each side: 4x = 40°
Divide each side by 4 : x = ?
It’s letter d
since m and n are parallel the measure of b will be equivalent to the angle 35 degrees