Question

AW.
3. Find the angles of the triangle whose sides are
x + y - 4 = 0, 2x + y - 6 = 0 and 5x + 3y - 15 = 0.​

Answer 1

sum of angles of triangle = 180

x + y - 4 + 2x + y - 6 + 5x + 3y - 15 = 0 + 0 + 0

x + 2x + 5x + y + y + 3y - 4 - 6 - 15 = 0

8x + 5y - 25 = 0

8x + 5y = 25

8x + y = 25 / 5

8x + y = 5

x + y = 5 / 8

up-to here I got it

I don't know the exact answer but I tried my best