Question

ANSWER FAST 50 POINTS PLEASE !!!

Answer 1

Line 1-Line 2-Associative property .

Line 2-Line 3- Distributive property

Solution:-

$\\ \rm\longmapsto (9+x)x$

$\\ \rm\longmapsto x(x+9)$

$\\ \rm\longmapsto x(9+x)$

$\\ \rm\longmapsto x^2+9$