You're meant to make one side of the equation equal 0.
For example, the first problem is

+ 9k = -7
You'd add 7 to both sides, leaving you with

+ 9k +7 =0
And I assume you know how to factor??
Answer:
(-2,-2)
Step-by-step explanation:
you would be going down the cooridante plane so that would only change the y value.
I don't know how to explain but the answer is 2.4.
Answer:
I don't have c but I do have a and b
Step-by-step explanation:
Part A)
Angle 3 is 103° because 77° + ∠3= 180° and ∠3 = 180° - 77° = 103°
Part B)
Angle 4 is 77° because ∠3 + ∠4 = 180° and ∠4 = 180° - 103° = 77°
These are the answers for k12