Step-by-step explanation:
it is a multiple of 21.
the highest common factor of 2 numbers is the longest combination of prime factors they have in common.
the prime factors of 21 are simply
3×7
if another number A shares this as the longest combination of prime factors, that means it contains 3×7 itself in its prime factors.
and that means this number A can only be a multiple of 3×7 (= 21), as other prime factors present would be the factor of 21.
Answer:
7n + 5 − 9n = 8 − 2n − 3 = true
-2 n + 5 = 5 - 2 n = true
Step-by-step explanation:
Left-hand side:
Simplify the following:
7 n - 9 n + 5
Grouping like terms, 7 n - 9 n + 5 = 5 + (7 n - 9 n):
5 + (7 n - 9 n)
7 n - 9 n = -2 n:
Answer: -2 n + 5
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Right-hand side:
Simplify the following:
-2 n - 3 + 8
Grouping like terms, -2 n - 3 + 8 = (8 - 3) - 2 n:
(8 - 3) - 2 n
8 - 3 = 5:
Answer: 5 - 2 n
7x +3 you add like terms which is 2x, and 5x that equals 7x the y’s cancel out. Then all you have left is 3
20 x 20 = 400
4(1/2 x 20 x 30) = 1200
400 + 1200 = 1600
So, D
