Answer:
13
Step-by-step explanation:
there is a rule that says that if you add any 2 sides, it should be more than the third. 9+21 is greater than 13. 21+13 is greater than 9. 13 is the only number which if you add 9 to it it will be greater than 21. 12 will equal 21, but it still wont work.
hope this helps :))
Answer:yes
Step-by-step explanation:
They are inverses if f( (g(x)) = x
f((g(x)) = (1/2) (2x + 4) - 2 = x + 2 - 2 = x
so this proves that g(x) is the inverse of f(x)
the other inverse g((f(x)) should also be = x
Answer:
Choice 4.
Step-by-step explanation:
f(g(x))
Replace g(x) with x^2+8 since g(x)=x^2+8.
f(g(x))
f(x^2+8)
Replace old input,x, in f with new input, (x^2+8).
f(g(x))
f(x^2+8)
2(x^2+8)+5
Distribute:
f(g(x))
f(x^2+8)
2(x^2+8)+5
2x^2+16+5
Combine like terms:
f(g(x))
f(x^2+8)
2(x^2+8)+5
2x^2+16+5
2x^2+21