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3 years ago

Solve the equation: -2/5 n = -30 A. n=-75 B. n=-12 C. n=12 D. n=75

2 answers:

6 0

Assuming your equation is: -2/5n = -30

-2/5n = -30 <- We get rid of the "/5n" by multiplying each side by 5n
-2 = -30 * 5n
-2 = -150n
-1 = -75n
75n = 1

But this doesn't match up with any of your answers, so if you wouldn't mind giving me the equation again, i'll work it out

Sonbull [250]3 years ago

5 0

two negatives make a positive, so the question is basically 2/5 x 30. 30/5 is 6, so 1/5 of 30 is 6. we want 2/5 so we double 1/5 and get 12. The correct answer is n.

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NEED HALP!!! Find the ordered pair $(s,t)$ that satisfies the system

satela [25.4K]

Answer:

(-8/7 ; 5/7)

Step-by-step explanation:

5t + 1/2s = 3 - - - (1)

3t - 6s = 9 - - - - - (2)

Multiply (1) by 12 and (2) by 1

Add the result to eliminate s

60t + 6s = 36

3t - 6s = 9

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63t = 45

t = 45 / 63

t = 5/7

Put t = 5/7 in either (1) or (2) to obtain the value of s

3(5/7) - 6s = 9

15/7 - 6s = 9

-6s = 9 - 15/7

-6s = (63 - 15)/7

-6s = 48/7

s = 48/7 * - 1/6

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2 years ago

You need exactly 47 bottles of water. You don’t want to buy more than you need, but you want the least expensive way. List the b

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Answer: That would be 1 case + 112 pack + 16 pack + 5 singles

Step-by-step explanation:

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2 years ago

Consider a nuclear power plant that produces 1200 MW of power and has a conversion efficiency of 34 percent (that is, for each u

cestrela7 [59]

Answer:

The amount of nuclear fuel required is 1.24 kg.

Step-by-step explanation:

From the principle of mass energy equivalence we know that energy generated by mass 'm' in an nuclear plant is

$E=m\cdot c^2$

where

'c' is the speed of light in free space

Since the power plant operates at 1200 MW thus the total energy produced in 1 year equals

$E=1200\times 10^6\times 3600\times 24\times 365=3.8\times 10^{16}Joules$

Thus using the energy produced in the energy equivalence we get

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3 years ago

Assignment<br>Solve: 4^3x=4^2

mart [117]

Answer:

x =2/3

Step-by-step explanation:

4^3x=4^2

Since the bases are the same, the exponents are the same

3x =2

Divide each side by 3

3x/3 = 2/3

x = 2/3

3 0

3 years ago

An executive invests 29,000, some at 8% and the rest at 7% annual interest. If he receives an annual return of $2,230, how much

jeka57 [31]

Answer:

Amount invested in A (8%) = $20,000

Amount invested in B (7%) = $9,000

Step-by-step explanation:

Given:

Total amount invested = $29,000

Interest rate A = 8% = 0.08

Interest rate B = 7% = 0.07

Annual return = $2,230

Find:

Amount invested in each

Computation:

Assume;

Amount invested in A = x

Amount invested in B = 29,000 - x

So,

Interest receive from A = x × 0.08

Interest receive from A = 0.08 x

Interest receive from B = (29000 - x) × 0.07

Interest receive from B = 2,030 - 0.07 x

Annual return = Interest receive from A + Interest receive from B

2,230 = 0.08 x + 2,030 - 0.07 x

x = 20,000

Amount invested in A = $20,000

Amount invested in B = 29,000 - $20,000

Amount invested in B = $9,000

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3 years ago