HELP MEEE PLEASE

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

Ineed no it anyone can see this

List x1, x2, x3, x4 where xi is the left endpoint of the four equal intervals used to estimate the area under the curve of f(x) between x = 4 and x = 6. a 4, 4.5, 5, 5.5 b 4.5, 5, 5.5, 6 c 4.25, 4.75, 5.25, 5.75 d 4, 4.2, 5.4, 6