Answer:
The equations shows a difference of squares are:
<u>10y²- 4x²</u> $ <u>6y²- x²</u>
Step-by-step explanation:
the difference of two squares is a squared number subtracted from another squared number, it has the general from Ax² - By²
We will check the options to find which shows a difference of squares.
1) 10y²- 4x²
The expression is similar to the general form, so the equation represents a difference of squares.
It can be factored as (√10 y + 2x )( √10 y - 2x)
2) 6y²- x²
The expression is similar to the general form, so the equation represents a difference of squares.
It can be factored as (√6y + x )( √6y - x)
3) 8x²−40x+25
The expression is not similar to the general form, so the equation does not represent a difference of squares.
4) 64x²-48x+9
The expression is not similar to the general form, so the equation does not represent a difference of squares.
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
Answer:
389 feets apart
Step-by-step explanation:
Given that:
Building A
Height = 400feets
Angle of elevation = 70°
Building B:
Height = 300 feets
Angle of elevation = 52°
Distance from the foot of building A to where Jonny is standing = x (see attached picture)
Using trigonometry :
Tanθ = opposite / Adjacent
Tan 70 = 400/ x
2.7474774x = 400
x = 145.58809 feets
Distance from the foot of building B to where Jonny is standing = y (see attached picture)
Using trigonometry :
Tanθ = opposite / Adjacent
Tan 52 = 300/ y
1.2799416y = 300
y = 145.59
y = 234.38568 feets
x + y = distance between the two buildings
(145.58809 + 234.38568) feets
= 379.97377
= 380 feets apart