What do I put on the top and bottom where the planks are

Tomas is making trail mix using granola and walnuts. he can spend a total of $12 on the ingredients. he buys 3 pounds of granola that costs $2.00 per pound. the walnuts cost $6 per pound. he uses the equation to represent the total cost, where x represents the number of pounds of granola and y represents the number of pounds of walnuts. he solves the equation for y, the number of pounds of walnuts he can buy. answer- b tomas added 6 to both sides of the equation instead of subtracting 6. just took the test

For f(x)=2x+3 and g(x)=x^2- 8 find (f+g) (x)

X-10/4 when x = –18 a 7 b –2 c –7 d 2