For 13th question,take the third vertex as (x , x+3) and substitute in the area of triangle formula

[y = x+3 is given]..on solving |4x-4| = 10 will be obtained

4x-4 = 10                                                                        4x-4 = -10

x = 7/2                                                                              x = -3/2 

substitute x=7/2 in y=x+3                                          substitute x= -3/2 in y= x+3

y = 13/2                                                                        y = 3/2

3rd vertex is ( 7/2,13/2)                                                3rd vertex is (-3/2,3/2)