Answer:
-16-7(2a+3)=23-2a
-23(2a+3)=23-2a
-16-7= 23
multiply -23 from 2a and +3
-46a [ we know - + always -] -69 =23 - 2a
-46a -69 = 23- 2a
-46a - 69 = 23-2a
-46a + 2a = 23 + 69
-44a = 92
a= -92/44