13-3*(x+1)=4-5x
13-3x-3=4-5x
2x=-6 |÷2
x=-3.
Ответ: противоположное число: 3.
6,3х-4-3(7,1х+0,3)=6,3х-4-21,3х-0,9=15х-4-0,9=15*2-4,9=30-4,9=25,1
X^2+5x+10-x^2+5x+3=1
5x+5x=1-10-3
10x^2=-12
x^2=-12:10
корней нет
Вариант 11
1) - p - k – a + 2a + k = - p + a
2) - (k – 2) – 2(2 - k) = - k + 2 - 4 + k = +2 - 4 = - 2
3) 4(3k – p) - ( – 2k + 3p) = 12k - 4p + 2k - 3p = 14k - 7p
<span>4) x + (7 – 3(x + 1)) = x + (7- 3x - 3) = x + 7 - 3x - 3 = - 2x - 4
</span>А-7. Домашнее задание по теме «Приведение подобных слагаемых»
Вариант 12:
1) 4h – 8f + 2f – 12h = - 8h - 6f
2) 3h – (– 2 + h) - 12 = 3h + 2 - h = 2h + 2
3) - (– 45k + 1) – 2(30k + 5) = + 45k - 1 - 60k - 10 = - 15k - 11
<span>4) x + 2 - (7x – 1 – (x + 2)) = x + 2 - (7x - 1 - x - 2) = x + 2 - 7x + 1 + x + 2 = 2x - 7x + 5 = - 5x + 5 = 5( - x + 1)
Вариант 13:
1) 5e – 4k – 10e – ( - 2e) = - 5e - 4k + 2e = - 3e - 4k
2) – (4 – k) + 3(k - 3) = - 4 + k + 3k - 9 = - 13 + 4k
3) – ( – 23a + y) + 12(2a + y) = 23a - y + 24a + 12y = 47a + 11y
<span>4) 3 - (4 – 2x – (x + 1)) = 3 - 4 + 2x + x + 3 = 2 + 3x
</span>Вариант 14:
</span>1) 2y - 12a – 14y + 10a = - 12y - 2a
2) – (3 – k) – 12(k + 12) = - 3k + k - 12k - 144 = - 14k - 144
3) – 12(y – 2a) + (– 3y + 5a) = - 12y + 24a - 3y + 5a = - 15y + 29a
<span>4) x + 1 – (5 + 2(x + 1)) = x + 1 - (5 + 2x + 2) = x + 1 - 5 - 2x - 2 = - x - 6</span><span>
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Удачи :)