Hey there!
Solve for k :
k = -15 ✅
18 = -k + 3
>> Substrat 3 from both sides :
18 - 3 = -k + 3 - 3
15 = -k
>> Dive each side by -1 :
15 / -1 = -k / -1
-15 = k
Therefore, your answer is k = -15
More about equations :
https://brainly.com/question/14440004
Have a good day :)
