The seventh child is fourteen years and seven month.
(1,2)....(2,-2)... now its making me write about 20 characters for some reason but anyways there is your answers i think buttt.... have a very nice day good luck on the rest of your school :)
For odd function f(-x)= -f(x)
1) f(-x)= sin(-x) = -sin(x)=-f(x) sin is odd function
2) f(-x) = sin(-2x) = -sin 2x=-f(x)
3) f(-x)= (-x)³+1 = -x³ +1 (not an odd function)To be an odd function, it should be like this:if a function is (x³+1), to be odd f(-x) should be -(x³+1)=-x³-14) f(x)= x/(x²+1)
f(-x) = (-x)/((-x)²+1)= -x/(x²+1)=-f(x)
So, f(-x) gives

,
that means that f(x)= x/(x²+1) is an odd function.
5)f(x) = ∛(2x)
f(-x) = ∛(2*(-x)=∛(2x*(-1)) = ∛(2x)*∛(-1)=
- ∛(2x)= -f(x)
Answer:
Step-by-step explanation:
2x+90=7x
2x=7x-90
2x-7x=-90
-5x+-90
x=18