Answer:
x = 4
Step-by-step explanation:
12/15=28/a which is a=35
then 35+28=63
14x+7=63 and x would be 4
their are 17 cows
7x2=14
82-14=68
68/4=17
(4-x) ( 7+ ×)
28 +4x -7x -x²
28 -3x - x²