Question

50 points :) 10x9=??

Answer 1

$\\ \sf\longmapsto 10\times 9$

$\\ \sf\longmapsto 90$

Note down below rules for sign notations

• (-)(-)=(+)
• (+)(-)=(-)(+)=(-)
• (+)(+)=(+)

Answer 2

• $\sf{90 }$

Step-by-step explanation:

• 10×9

• 90