Question

mim agudem com as expresoes, por favo e muito importante 
7x-5=3x-1
6x+8=4x-2
10x+5=7x-1

Answer 1

Vou responder as duas últimas:

$6x + 8 = 4x - 2 \\ 6x - 4x = -2-8 \\ 2x = -10 \\ x = \frac{-10}{2} \\ \\ x = -5 \\ \\ \\ \\ 10x + 5 = 7x - 1 \\ 10x-7x = -1-5 \\ 3x = -6 \\ x = \frac{-6}{3} \\ \\ x = -2$

Frações:

$\frac{8}{7} : \frac{3}{6} = \frac{8}{7}* \frac{6}{3} = \frac{48}{21} = \frac{16}{7} \\ \\ \frac{5}{5}* \frac{3}{8} = \frac{5*3}{5*8} = \frac{15}{40} = \frac{3}{8} \\ \\ \frac{6}{4}: \frac{5}{2} = \frac{6}{4} * \frac{2}{5} = \frac{12}{20} = \frac{3}{5} \\ \\ \frac{6}{3}* \frac{1}{5} = \frac{6*1}{3*5} = \frac{6}{15} = \frac{2}{5}$

Answer 2

Na primeira
7x-5=3x-1
7x-3x=-1+5
4x=4
x=4/4
x=1

na segunda
6x+8=4x-2
6x-4x=-2-8
2x=-10
x=-10/2
x=-5

Na terceira
10x+5=7x-1
10x-7x=-1-5
3x=-6
x=-6/3
x=-2