Question

1) Упростить: 1.1) 3a - 4b + 5c + 7b + 4a - 4c = ? 1.2) 3x - 4y + 5z - 3x + 4y + 5z = ? 2) Вычислить дроби и сократить: 2.1) 3/4 + 5/4 = ? 2.2) 12/17 - 8/17 = ? 2,3) 3/5 + 2/7 = ? 2.4) 3/7 - 5/21 = ? ПЖ СРОЧНО 100 БАЛЛОВ!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Answer 1

Я сразу буду писать ответ.
1).
1.1) 7а+3b-c
1.2) 0
2).
2.1) 8/4=2
2.2) 4/17
2.3) 21/35+10/35= 56/35=8/7= 1 1/7
2.4) 9/21-5/21= 4/21
На счёт третьего пункта второго задания не уверена.

Answer 2

1) Упростить: 3a + 4b + 5c + 7b + 4a - 4c = ?

To simplify the given expression, we can combine like terms. Like terms are terms that have the same variables raised to the same powers.

In this case, we have the following like terms: - 3a and 4a - 4b and 7b - 5c and -4c

Combining these like terms, we get: 3a + 4b + 5c + 7b + 4a - 4c = (3a + 4a) + (4b + 7b) + (5c - 4c) = 7a + 11b + c

Therefore, the simplified expression is 7a + 11b + c. [[1]]

2) Вычислить дроби и сократить:

2.1) 3/4 + 5/4 = ? To add fractions, we need to have a common denominator. In this case, the denominators are already the same, so we can simply add the numerators: 3/4 + 5/4 = (3 + 5)/4 = 8/4 = 2

Therefore, the sum of 3/4 and 5/4 is 2. [[2]]

2.2) 12/17 - 8/17 = ? To subtract fractions, we also need a common denominator. In this case, the denominators are already the same, so we can subtract the numerators: 12/17 - 8/17 = (12 - 8)/17 = 4/17

Therefore, the difference between 12/17 and 8/17 is 4/17. [[3]]

2.3) 3/5 + 2/7 = ? To add fractions with different denominators, we need to find a common denominator. In this case, the least common multiple (LCM) of 5 and 7 is 35. We can then convert the fractions to have a denominator of 35: 3/5 + 2/7 = (3 * 7)/(5 * 7) + (2 * 5)/(7 * 5) = 21/35 + 10/35 = 31/35

Therefore, the sum of 3/5 and 2/7 is 31/35. [[4]]

2.4) 3/7 - 5/21 = ? To subtract fractions with different denominators, we need to find a common denominator. In this case, the least common multiple (LCM) of 7 and 21 is 21. We can then convert the fractions to have a denominator of 21: 3/7 - 5/21 = (3 * 3)/(7 * 3) - (5 * 1)/(21 * 1) = 9/21 - 5/21 = 4/21

Therefore, the difference between 3/7 and 5/21 is 4/21. [[5]]

I hope this helps! Let me know if you have any further questions.