Answer:
the daimeter of the heart of the heart of the heart
Answer:
1370
Step-by-step explanation:
<h3>Given</h3>
- AP with d= 7 and a₂₂ = 149
<h3>To find</h3>
<h3>Solution</h3>
<u>First, let's get the value of the first term:</u>
- aₙ = a + (n-1)d
- a₂₂ = a + 21d
- 149 = a + 21*7
- a = 149 - 147
- a= 2
<u>Next, let's find the sum of the first 20 terms</u>
- Sₙ = 1/2n(2a+ (n-1)d)
- S₂₀ = 1/2*20(2*2 + 19*7) = 10(4 + 133) = 10*137 = 1370
<u>Answer is</u> 1370
Answer:
True
Step-by-step explanation:
The equation of direct variation is
y = kx ← k is the constant of variation
To find k divide both sides by x
= k
That is the constant is the ratio of y- values to x- values
Answer:
a = length of the base = 2.172 m
b = width of the base = 1.357 m
c = height = 4.072 m
Step-by-step explanation:
Suppose we want to build a rectangular storage container with open top whose volume is 12 cubic meters. Assume that the cost of materials for the base is 12 dollars per square meter, and the cost of materials for the sides is 8 dollars per square meter. The height of the box is three times the width of the base. What’s the least amount of money we can spend to build such a container?
lets call a = length of the base
b = width of the base
c = height
V = a.b.c = 12
Area without the top:
Area = ab + 2bc + 2ac
Cost = 12ab + 8.2bc + 8.2ac
Cost = 12ab + 16bc + 16ac
height = 3.width
c = 3b
Cost = 12ab + 16b.3b + 16a.3b = 12ab + 48b² + 48ab = 48b² + 60ab
abc = 12 → ab.3b = 12 → 3ab² = 12 → ab² = 4 → a = 4/b²
Cost = 48b² + 60ab = 48b² + 60b.4/b² = 48b² + 240/b
C(b) = 48b² + 240/b
C'(b) = 96b - 240/b²
Minimum cost: C'(b) = 0
96b - 240/b² = 0
(96b³ - 240)/b² = 0
96b³ - 240 = 0
96b³ = 240
b³ = 240/96
b³ = 2.5
b = 1.357m
c = 3b = 3*1.357 = 4.072m
a = 4/b² = 2.172m