You don't know your terms I suppose.
Arithmetic: goes from one term to the next by adding or subtracting the same amount
Ex. 3,12,21,30,39 (d=9)
(d means difference, use this for arithmetic sequences)
Geometric: goes from one term to the next by multiplying or dividing by the same amount
Ex. 1,2,4,8,16,32,64,128 (r=2) (r means ratio, its just the number multiplied or divided each time)
Answer is c
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
There is no one answer (ordered pair) to this equation and the answer is found by graphing or trying out different values for each variable. Anyway, here are some solutions; (1,0), (4,1), (0,-1/3).
To find the answer to -10x=-210 you must divide -210 by -10
-210/-10= 21
Therefore x=21
So the proper equation is -10(21)=-210