N^2 = 24 + 2n
n^2 - 2n - 24 = 0
(n-6)(n+4) = 0
n = 6 , n = - 4
(4*7/2)+(15*7)+(7*6/2) = 140
Answer:
After 1 year, both the tress will be of the same height.
Step-by-step explanation:
Let us assume in x years, both trees have same height.
Type A is 7 feet tall and grows at a rate of 8 inches per year.
⇒The growth of tree A in x years = x times ( Height growth each year)
= 8 (x) = 8 x
⇒Actual height of tree A in x years = Initial Height + Growth in x years
= 7 + 8 x
or, the height of tree A after x years = 7 + 8x
Type B is 9 feet tall and grows at a rate of 6 inches per year.
⇒The growth of tree B in x years = x times ( Height growth each year)
= 6 (x) = 6 x
⇒Actual height of tree B in x years = Initial Height + Growth in x years
= 9 + 6 x
or, the height of tree B after x years = 9 + 6x
According to the question:
After x years, Height of tree A =Height of tree B
⇒7 + 8x = 9 + 6x
or, 8x - 6x = 9 - 7
or, 2 x = 2
or, x = 2/2 = 1 ⇒ x = 1
Hence, after 1 year, both the tress will be of the same height.
C. He forgot to place a zero in the quotient.
see attachment:
