Answer:
x = 23 degrees
Because if you look at diagram x is vertical to angle FBC, and angle FEC and angle EBA are alternate interior angles so they are equal to each other, and AC is a straight line which means it equals to 180 degrees.

x = 23 degrees
The slope is change in "Y" divided by the change in "x"
1-(-3)/2-(-1)
= 4/3
Standard Form
y-y1=m(x-x1)
y-(-3)=4/3(x-(-1)
y+3=4/3x+4/3
y=4/3x-5/3
Rewrite in standard form
-4/3x+y=-5/3
Can't have fractions so multiply by 3 to get rid of the denominator
-4x+3y=5
Divide by -1 to get rid of the negative sign
4x-3y=-5