Answer :

Let the size of one angle be x
so the size of another angle = 3x-5
sum of the two angles = 143 degrees
so, x + 3x - 5 = 143
or, 4x = 143+5
or, x = 149/4 = 37.25 degrees
other angle = 3*37.25-5 = 106.75 degrees
let the another angle be x ,then first angle will be 3*x-5
according to the question
x + 3*x-5 =143'
x+3*x=143+5
4*x=148
x=148/4
x=37'
another angle = x  =37'
first angle = 3x-5 = 3*37-5 = 111-5 = 106'