Question

Se considera functia f:R->R , f(x)=3x-2
Determinati numarul real a stiind ca punctul T(a, 2a+4) apartine graficului functiei f

Answer 1

$\sf f: \mathbb R \rightarrow \mathbb R \\ f(x)=3x-2 \\ T(a;2a+4) \in G_f \Longrightarrow \\ f(a)=2a+4(1) \\ f(a)=3a-2(2) \\ Din~(1)~si~(2) \Longrightarrow \\ 2a+4=3a-2 \\ 3a-2a=4+2 \\ \boxed{\sf a=6}$

Answer 2

f:R->R , f(x)=3x-2T(a, 2a+4)∈Gf<=>f(a)=2a+4
f(a)=3a-2➯3a-2=2a+4<=>
                3a-2a=2+4<=>
                a=6