Coefficient of x in (x+9)(8−5x) is:

Let's expand the given expression (x+9)(8−5x) by multiplying the terms:
(x+9)(8−5x)=x(8)+x(−5x)+9(8)+9(−5x)
=8x−5x
2
+72−45x
Combine the like terms (the terms containing x):

=−5x
2
+(8x−45x)+72
=−5x
2
−37x+72
The coefficient of x in this polynomial expression is −37.