Question

Me ajudem pfvrr
Resolva as equações fracionárias:
a) 2x+x/3=7
b)x/3+2/5=3/4
c)x/4+x/3=1/2
d)2x/4-2/5=x/3+1/2
e)2x/6+x/3=7/2+2x/4

Answer 1

Resposta:

a) 2x+x/3=7

$\frac{2x + x}{3} = 7 \\ \\ \frac{3x}{3} = 7 \\ \\ x = 7$

b)x/3+2/5=3/4

$\frac{x}{3} + \frac{2}{5} = \frac{3}{4} \\ \\ \frac{20x + 24 = 45}{60} \\ \\ 20x + 24 = 45 \\ 20x = 45 - 24 \\ 20x = 21 \\ \\ x = \frac{21}{20}$

c)x/4+x/3=1/2

$\frac{x}{4} + \frac{x}{3} = \frac{1}{2} \\ \\ \frac{3x + 4x = 6}{12} \\ \\ 3x + 4x = 6 \\ 7x = 6 \\ \\ x = \frac{6}{7}$

d)2x/4-2/5=x/3+1/2

$\frac{2x}{4} - \frac{2}{5} = \frac{x}{3} + \frac{1}{2} \\ \\ \frac{30x - 24 = 20x + 3 0}{60} \\ \\ 30x - 24 = 20x + 30 \\ 30x - 24 - 20x - 30 = 0 \\ 10x - 54 = 0 \\ \\ 10x = 54 \\ \\ x = \frac{54}{10} \div (2) \\ \\ x = \frac{27}{5}$

e)2x/6+x/3=7/2+2x/4

$\frac{2x}{6} + \frac{x}{3} = \frac{7}{2} + \frac{2x}{4} \\ \\ \frac{4x + 4x = 42 + 6x}{12} \\ \\ 4x + 4x = 42 + 6x \\ 8x - 42 - 6x = 0 \\ 2x - 42 = 0 \\ 2x = 42 \div (2) \\ x = 21$