Question

Como fazer essa questao???

Answer 1

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$\frac{2}{4} = \frac{3}{x} \\ \\ 2x=12 \\ \\ x=12\div2 \\ \\ x=6$

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$\frac{4}{12} = \frac{x}{21} \\ \\ 12x=84 \\ \\ x=84\div12 \\ \\ x=7$

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$\frac{x}{14} = \frac{9}{12} \\ \\ 12x=126 \\ \\ x=126\div12 \\ \\ x=10,5$

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$\frac{8}{2x-6} = \frac{12}{x+1} \\ \\ 12(2x-6)=8(x+1) \\ \\ 24x-72=8x+8 \\ \\ 24x-8x=8+72 \\ \\ 16x=80 \\ \\ x=80\div16 \\ \\ x=5$