Let x be the no. of seconds it takes for the balloons to be at the same height.
7+3x = 12+2x
Deduct both sides by 2x.
7+x = 12
Deduct both sides by 7.
x = 5
Ans: It will take 5 seconds for the balloons to be at the same height.

4 0

3 years ago

What is the ratio of the intensities of an earthquake PP wave passing through the Earth and detected at two points 19 kmkm and 4

Tamiku [17]

Answer:

The ratio of the intensities is roughly 6:1.

Step-by-step explanation:

The intensity I() of an earthquake wave is given by:

$I = \frac{P}{4\pi d^{2}}$

<em>where P: is the power ans d: is the distance. </em>

Hence, the ratio of the intensities of an earthquake wave passing through the Earth and detected at two points 19 km and 46 km from the source is:

$\frac{I_{1}}{I_{2}} = \frac{P/4\pi d_{1}^{2}}{P/4\pi d_{2}^{2}}$

<em>where I₁ = P/4πd₁², d₁=19 km, I₁ = P/4πd₂² and d₂=46 km </em>

$\frac{I_{1}}{I_{2}} = \frac{d_{2}^{2}}{d_{1}^{2}}$

$\frac{I_{1}}{I_{2}} = \frac{46 km^{2}}{19 km^{2}}$

$\frac{I_{1}}{I_{2}} = 5.9:1$

Therefore, the ratio of the intensities is roughly 6:1.

I hope it helps you!

3 0

3 years ago

Substitution method need help for home work

Marizza181 [45]

-3y = x...so we sub in -3y for x in the other equation

-x + 7y = 70
-(-3y) + 7y = 70
3y + 7y = 70
10y = 70
y = 70/10
y = 7

so we sub in 7 for y in either of the original equations to find x
-3y = x
-3(7) = x
-21 = x

so ur solution is (-21,7)

6 0

3 years ago