Answer:
Step-by-step explanation:
That will be the perimeter. Perimeter is the distance around. Add all five sides, be sure to put the unit behind.
I need more information to help any further.
Answer:
f(x)=x^2+3
f(x+y)=(x+y)^2+3
this is done by replacing x with (x+y)
f(x+y)=x^2+2xy+y^2+3
therefore : f(x+y)= x^2+y^2+2xy+3
117
Step-by-step explanation:
(x+3) is 13 because x is 10 so 10+3 is 13 and then 9 so 13×9 is 117