Question

1.найти значение выражение
а)3,8*4,5+1,9
б)3*10^-2+4*10^-3+2*10^-1
2.Решие уравнение
7+12x=11-8x
3.(корень 99-корень 11)*корень 11

Answer 1

1.

а)

$3.8 times 4.5 + 1.9 = 17.1 + 1.9 = 19$

б)

$3 times 10 {}^{ - 2} + 4 times 10 {}^{ - 3} + 2 times 10 {}^{ - 1} =3 times frac{1}{100} + 4 times frac{1}{1000 } + 2 times frac{1}{10} = 0.03 + 0.004 + 0.2 = 0.234$

2.

$7 + 12x = 11 - 8x \ 12x + 8x = 11 - 7 \ 20x = 4 \ x = frac{4}{20} = frac{1}{5} = 0.2$

3.

$(sqrt{99} - sqrt{11} ) times sqrt{11} = (3 sqrt{11} - sqrt{11} ) times sqrt{11} = 2 sqrt{11} times sqrt{11} = 2 times 11 = 22$

Answer 2

1) 3,8×4,5+1,9=19. 2)7+12х=11-8х

Answer 3

7+12х=11-8х

Answer 4

12х+8х=11-7

Answer 5

20х=4 х=0,2