Answer:
<em>a </em>- 13
Step-by-step explanation:
a- 13 because you are taking 13 away from a
B) (16 + 20)a - 18b
16a and 20a are both positive and 18b is the only negative it’s easier to add the positive with each other then the negative and a positive then add other positive
Y=4x-5... if you were asking for that in words
