Determine if 9x2 - 42x + 49 can be the area of a square. If so, what would the value of x have to be if the area of the square i
1 answer:
You might be interested in
9514 1404 393
Answer:
2 nickels, 9 dimes
Step-by-step explanation:
When there are a number of overlapping shaded areas on the graph, I find it convenient to use the reverse of the inequalities. That makes the <em>unshaded</em> area the solution space. Here, the vertices of the triangular solution space are ...
(2, 9), (2, 13), (6, 9)
Any of the grid points within (or on) this triangle is a possible solution. One of them is (2, 9) corresponding to 2 nickels and 9 dimes.
__
Three solutions are shown:
(x, y) = (2, 9), (3, 10), (4, 11)
Answer:
150.51 dB
Step-by-step explanation:
Data provided in the question:
decibel level of sound at 161 km distance = 180 dB
d₁ = 161 km
d₂ = 4800 km
I₁ = 180 db
The formula for intensity of sound is given as:
I =
and the relation between intensity and distance is given as:
I ∝
or
Id² = constant
thus,
I₁d₁² = I₂d₂²
or
therefore,
I =
or
I =
or
I = 20 × (-1.474)
or
I = -29.49
Therefore,
the decibel level on Rodriguez Island, 4,800 km away
= 180 - 29.49
= 150.51 dB