Question

Find the value of x that make it true

Answer 1

Answer:

Step-by-step explanation:

1). 10 = $\frac{1+7x}{7+x}$

   10(7 + x) = 1 + 7x

   70 + 10x = 7x + 1

   10x - 7x = 1 - 70

   3x = -69

   x = -23

2). 0.2 = $\frac{6+2x}{12+x}$

    0.2(12 + x) = 6 + 2x

    2.4 + 0.2x = 6 + 2x

    2.4 - 6 = 2x - 0.2x

    1.8x = -3.6

    x = -2

3). 0.8 = $\frac{x}{x+0.5}$

    0.8(x + 0.5) = x

    0.8x + 0.4 = x

    x - 0.8x = 0.4

    0.2x = 0.4

    x = 2

4). 3.5 = $\frac{4+2x}{0.5-x}$

    3.5(0.5 - x) = 4 + 2x

    1.75 - 3.5x = 4 + 2x

    -3.5x - 2x = 4 - 1.75

    -5.5x = 2.25

     x = -$\frac{2.25}{5.5}$

     x = - $\frac{9}{22}$