Respuesta :
Answer:
12a + 3b.
Step-by-step explanation:
3(4a + b)
= 3 * 4a + 3 * b
= 12a + 3b.
Hope this helps!
Answer:
[tex]12a+3b[/tex]
Step-by-step explanation:
[tex]\mathrm{Apply\:the\:distributive\:law}:\quad \:a\left(b+c\right)=ab+ac\\a=3,\:b=4a,\:c=b\\=3\times \:4a+3b\\\mathrm{Multiply\:the\:numbers:}\:3\times \:4=12\\=12a+3b[/tex]