Question

pls answer to question 9 , 10 , 11 and 12​

Answer 1

it's not clear..............

Answer 2

Step-by-step explanation:

9) Let the first prize be x.

Second prize = 5/6 × x = 5/6x

Third prize = 4/5 × 5/6x = 2/3x

The total prize = 2/3x + 5/6x + x = 2½x

We equate this to 150.

2½x = 150

x = 150/2.5

x = 60

First prize = 60

Second prize = 60 × 5/6 = 50

Third prize = 2/3 × 60 = 40

10) (x² - 9) / (5 + x²) = - 5/9

9(x² - 9) = - 5(5 + x²)

9x² - 81 = - 25 - 5x²

9x² + 5x² = 81 - 25

14x² = 56

x² = 56/14 = 4

x = 2

11) (x + b)/(a - b) = (x - b) / (a + b)

(x + b)(a + b) = (x - b)(a - b)

ax + bx + ab + b² = ax - ab - bx + b²

ax - ax + bx + bx + ab + ab + b² - b² = 0

2bx + 2ab = 0

2b(x + a) = 0

2b = 0/(x + a)

2b = 0

b = 0

12) (x + 2)/3 - (x + 2)/5 = (x - 3)/4 - 1

5 × 4(x + 2) - 3 × 4(x +1) = (x - 3)3 × 5 - 1(3 × 5 × 4)

20(x + 2) - 12(x + 1) = (x - 3)15 - 60

20x + 40 - 12x - 12 = 15x - 45 - 60 + 12

20x - 12x - 15x = - 40 - 45 - 60 + 12

-7x = - 133

x = 133/7 = 19