The first 3 terms are a, ar and ar^2
so a + ar + ar^2 = 7a
a + ar + ar^2 + ar^3 = 45
7a + ar^3 = 45
a(7 + r^3) = 45
a = 45/(7 + r^3)
Because we know the sequence are positive integers r must be a natural number.
(7 + r^3) is a factor of 45 [ie 1, 3, 5, 9, 15, 45]
so r = 2 because 7 + 2^3 = 15 is the only factor possible
a = 45/15 = 3
Answer:
A -60i - 14j
Step-by-step explanation:
u = -9i + 8j
v = 7i + 5j
2u = 2(-9i + 8j) = -18i + 16j
6v = 6(7i + 5j) = 42i + 30j
2u - 6v
(-18i + 16j) - (42i + 30j)
(-18i - 42i) + (16j-30j)
-60i - 14j
The answer is d vvvvvvvvvvvvvvvv
6^2 is the correct answer
Answer: There are 20 goats and 18 chikens.
Step-by-step explanation:
Hi, to answer this question we have to write a system of equations:
If the number of chickens is represented by C, and the number of goats is G.
Total of Animals equation:
a)C+ G = 38
Total of legs equation (since chickens have 2 legs and goats have 4 ):
b)2C + 4 G =116
If we multiply a) by 2 and subtract a) from b).
<em>2C + 4 G =116
</em>
<em>-
</em>
<em>2C + 2 G =76
</em>
<em>_________
</em>
<em>2G = 40
</em>
G = 40/2
G= 20
Replacing the value of G on any equation:
a) C+ (20) =38
C =38-20
C=18
There are 20 goats and 18 chickens.
