Question

DESENHE O GRÁFICO DA FUNÇÃO:. F(X) = 3x+9. por favor Me ajudem​

Answer 1

$\large\boxed{\begin{array}{l}\underline{\rm Func_{\!\!,}\tilde ao\,de\,1^o\,grau}\\\sf \acute E\,toda\,func_{\!\!,}\tilde ao\,que\,assume\,a\,forma\\\sf f(x)=ax+b\,onde\,a,b\in\mathbb{R},a\ne0.\\\sf a\longrightarrow coeficiente\,angular\\\sf b\longrightarrow coeficiente\,linear\end{array}}$

$\large\boxed{\begin{array}{l}\underline{\rm Representac_{\!\!,}\tilde ao\,no\,plano\,cartesiano.}\\\sf No\,plano\,cartesiano\,sua\,representac_{\!\!,}\tilde ao\\\sf \acute e\,uma\,reta\,inclinada.\\\sf se\,a>0\longrightarrow func_{\!\!,}\tilde ao\,crescente\\\sf se\,a<0\longrightarrow func_{\!\!,}\tilde ao\,decrescente\\\sf Uma\,reta\,fica\,determinada\,por\,2\,pontos.\\\sf \acute e\,usual\,conhecer\,os\,principais\,pontos.\end{array}}$

$\large\boxed{\begin{array}{l}\underline{\rm Intersecc_{\!\!,}\tilde ao\,com\,o\,eixo\,y}\\\sf Basta\,fazer\, x=0\,e\,calcular\,o\,valor\,de\,y.\\\sf o\,ponto\,assume\,a\,forma\, A(0,y).\\\underline{\rm intersecc_{\!\!,}\tilde ao\,com\,eixo\,x}\\\sf Basta\,fazer\,y=0\,e\,calcular\,o\,valor\,de,x.\\\sf o\,ponto\,assume\,a\,forma\, B(x,0)\end{array}}$

$\large\boxed{\begin{array}{l}\sf f(x)=3x+9\\\sf a=3>0\longrightarrow func_{\!\!,}\tilde ao\,crescente\\\underline{\rm intersecc_{\!\!,}\tilde ao\,com\,eixo\,y}\\\underline{\rm fac_{\!\!,}a\,x=0}\\\sf f(0)=3\cdot0+9\\\sf f(0)=9\longrightarrow A(0,9).\\\underline{\rm intersecc_{\!\!,}\tilde ao\,com\,eixo\,x}\\\underline{\rm fac_{\!\!,}a\,y=0}\\\sf 3x+9=0\\\sf 3x=-9\\\sf x=-\dfrac{9}{3}\\\\\sf x=-3\longrightarrow B(-3,0)\\\sf Basta\,marcar\,esses\,pontos\,e\,trac_{\!\!,}ar\,o\,gr\acute afico. \end{array}}$