Respuesta :

Answer:

2.1

Step-by-step explanation:

[tex]3.4-2.8d+2.8d-1.3\\\\\mathrm{Add\:similar\:elements:}\:-2.8d+2.8d=0\\\\=3.4-1.3\\\\\mathrm{Subtract\:the\:numbers:}\:3.4-1.3\\\\=2.1[/tex]

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