Answer:
Length = 175
Width = 125
Step-by-step explanation:
P=2(L+W)
600ft=2(L+W)
300=L+W
300=2W-75ft+W
375=3W
125=W
L=2W-75
L=2(125)-75
L=250-75
L=175
Answer:
The temperature of the liquid 15 minutes later is 
Step-by-step explanation:
This is an example of arithmetic progression
We need to find 15 th term
Here

Answer:
x ≈ 14.7
Step-by-step explanation:
Assuming the triangle is right then use Pythagoras' identity.
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
x² + 15² = 21²
x² + 225 = 441 ( subtract 225 from both sides )
x² = 216 ( take the square root of both sides )
x =
≈ 14.7 ( to the nearest tenth )
Here, it helps to find a general expression for the nth term in the
sequence. Since the sequence is arithmetic, the general term is a_n = a +
bn, where b is the common difference. By inspection of the first few
terms we see the common difference is -4. Then by solving a_1 = a - 4x1 =
5, we obtain a = 9, so the nth term is: a_n = 9-4n. We then solve
a_n=-111 for n, so 9-4n=-111. Rearranging, we get 4n=9+111, or 4n=120,
or n=30. Thus there are 30 terms in the sequence.
The sum of the angles of the triangle is 180 degrees, so:
(x + 70) + 76 + 41 = 180
(x + 70) + 117 = 180
x + 70 = 63
x = -7
Hope that helps!