Answer:
Bottom left graph, ∠a + ∠b = 180°, ∠a + ∠b = 90°, ∠a + ∠b = 90°
Explanation:
For the first problem, we can look at the slope. The slope of the equation is negative. The line has to be similar to the bottom slant of the letter "K".
There are two lines that are similar and have the same y-intercept, so it's just a matter of which slope matches.
The slope is -1, so that means to find a different point we go down 1 and right 1.
The only point that's the same on the two lines are (0, 3).
When go down 1 and right 1, the point should be: (1,2)
The only line that satisfy this is the bottom left graph.
For problem 2, ∠a and ∠b must add up to 180°.
So the equation for problem 2 is: ∠a + ∠b = 180°
For problem 3, ∠a and ∠b are equal because they're opposite angles.
So the equation for problem 3 is: ∠a = ∠b
For problem 4, ∠a and ∠b must add up to 90°.
So the equation for problem 4 is: ∠a + ∠b = 90°
For problem 5, ∠a and ∠b must add up to 90°, since the other angle is 90°, which is half to 180°.
So the equation for problem 5 is: ∠a + ∠b = 90°