Question

3a+ 4c + 9c – 7b – 7a- 15c = -4a -2c -7b

Answer 1

$3a+ 4c + 9c - 7b - 7a- 15c = -4a -2c -7b \\ Simplificamos y resolvemos: \\ \\ -\not4a-2c-7b+\not4a= -2c -7b \\ \\ -2c-7b= -2c-7b \\ \\ -7b= -\not2c-7b+\not2c \\ \\ -7b= -7b \\ \\ b= \dfrac{-7}{-7} \\ \\ \boxed{\boxed{\textbf{b= 1 }\Longrightarrow \textbf{b= b}}}$

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