Respuesta :

[tex]f\left( x \right) =-2x+8\\ \\ g\left( x \right)=3x[/tex]

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[tex]f\left( x \right) +g\left( x \right) =-2x+8+3x=x+8[/tex]

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Therefore:

[tex]\left( f+g \right) \left( -1 \right) =\left( -1 \right) +8=7[/tex]
good job