Answer:
Option C. 10.5(12 + x) square feet
Option E. (126 + 10.5x) square feet
Step-by-step explanation:
step 1
Find the area of the original living room
we know that
The area of the original living room is equal to
[tex]A=LW[/tex]
we have
[tex]L=12\ ft\\W=10\frac{1}{2}\ ft=10.5\ ft[/tex]
substitute
[tex]A=(12)(10.5)=126\ ft^2[/tex]
step 2
Find the new area of the living room
The length of the room is being expanded by x feet
so
we have
[tex]L=(12+x)\ ft\\W=10.5\ ft[/tex]
The new area is
[tex]A=10.5(12+x)\ ft^2[/tex]
The expanded form of the expression is
Apply distributive property
[tex]A=10.5(12)+10.5(x)\\A=(126+10.5x)\ ft^2[/tex]