To find a positive and a negative angle coterminal with a given angle, you can add and subtract 360°.
They cancel each other out because one is + and the other is -.
Answer:
x + y = 1
Step-by-step explanation:
The equation of straight line with X intercept (d,0) and Y intercept (0,d) is given in the intercept form as
......... (1)
Now, the point (-3,4) is on this straight line, so it will satisfy equation (1).
Hence, 
⇒ d = - 3 + 4 = 1.
Therefore, the equation of the straight line becomes x + y = 1. (Answer)