Question

va rog frumos dau 25 de puncte

Answer 1

a) (x+3)/4  = 7/2
    2(x+3) = 4x7
   2x + 6 = 28
   2x = 22
   x = 11

b) 9/(x+5) = 3/2
    3(x+5) = 9x2
    3x+ 15 = 18
    3x = 3
    x = 1

c) (x-7)/9 = 4/3
    3(x-7) = 4x9
    3x - 21 = 36
    3x = 57
    x = 19

d) 3/5 = 9/(x+5)
    3(x+5) = 5x9
    3x + 15 = 45
    3x = 30
    x = 10

Answer 2

$a.\frac{x+3}{4}=\frac{7}{2} \\ \\2(x+3)=7\cdot4 \\ \\ 2x+6=28 \\ \\ 2x=28-6 \\ \\ 2x=22 \\ \\ x=11$

$b.\frac{9}{x+5}=\frac{3}{2} \\ \\9\cdot2=3(x+5) \\ \\ 18=15+3x \\ \\ 18-15=3x \\ \\ 3=3x \\ \\ x=1$

$c.\frac{x-7}{9}=\frac{4}{3} \\ \\3(x-7)=4\cdot9 \\ \\ 3x-21=36 \\ \\ 3x=36+21 \\ \\ 3x=57 \\ \\ x=57:3 \\ \\ x=19$

$d.\frac{3}{5}=\frac{9}{x+5} \\ \\3(x+5)=5\cdot9 \\ \\3x+15=45 \\ \\ 3x=45-15 \\ \\ 3x=30 \\ \\ x=10$