Using two points to find the slope use
y2-y1/x2-x1
i chose points (0,4) and (2,14)
14-4/2-0
10/2
5
The slope is 5
1+2i
to find the midpoint you do it just like you did with rectangular coordinates,
add and divide by 2 the real component and the imaginary components.

and
Answer:
x=1
Step-by-step explanation:
55+70=125
sum of angles in a triangle is 180 so
180-125=55
54x+1=55
x=1
About 3.
hope this helped! :)
By finding like denominators, you can add the fractions on each side. Then, compare by cross multiplying.