Answer:
35
Step-by-step explanation:
if you multiply all of the numbers in the first boxes by five, those numbers would be correct. So if you multiply 7 by 5, your answer would be 35
adding the 2 equations eliminates x and gives:-
5y = 60
y = 12
Plug y = 12 into the first equation:-
2x + 3(12) = 40
2x = 40 - 36 = 4 so x = 2
Answer is x = 2 and y = 12.
This is the sum of the arithmetic sequence:
10 - 2 + 6 + 14 + ... + 110
where: a 1 = - 10, d = 8
a n = 110
a n = a 1 + ( n - 1 ) * d
110 = - 10 + ( n - 1 ) * 8
110 = - 10 + 8 n - 8
110 + 10 + 8 = 8 n
128 = 8 n
n = 128 : 8
n = 16
∑ n = n/2 * ( a 1 + a n )
∑ 16 = 16/2 * ( -10 + 110 ) = 8 * 100 = 800
Answer:
The sum is 800.
27$ because you do 20*15*12 then 3600*0.09 and divide that answer by 12 which is 27
