Answer:
x²+8x+15
Step-by-step explanation:
Use FOIL method
( x + 5 ) ( x + 3 )
( x ) ( x ) + ( x ) ( 3 ) + ( 5 ) ( x ) + ( 5 ) ( 3 )
x² + 3x + 5x + 15
x² + 8x + 15
