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3 years ago

4x+7y=- 20 2x-5 y=-10

Mathematics

1 answer:

Diano4ka-milaya [45]3 years ago

5 0

Answer:

x = -5 , y = 0

Step-by-step explanation:

Solve the following system:

{4 x + 7 y = -20 | (equation 1)

2 x - 5 y = -10 | (equation 2)

Subtract 1/2 × (equation 1) from equation 2:

{4 x + 7 y = -20 | (equation 1)

0 x - (17 y)/2 = 0 | (equation 2)

Multiply equation 2 by 2/17:

{4 x + 7 y = -20 | (equation 1)

0 x - y = 0 | (equation 2)

Multiply equation 2 by -1:

{4 x + 7 y = -20 | (equation 1)

0 x+y = 0 | (equation 2)

Subtract 7 × (equation 2) from equation 1:

{4 x+0 y = -20 | (equation 1)

0 x+y = 0 | (equation 2)

Divide equation 1 by 4:

{x+0 y = -5 | (equation 1)

0 x+y = 0 | (equation 2)

Collect results:

Answer: {x = -5 , y = 0

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zmey [24]

Alrighty

squaer base so length=width, nice

v=lwh
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and volume is 32000
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alrighty

we gots
SA=W²+4HW and
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we want to minimize the square foottage
get rid of one of the variables
32000=W²H
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take derivitive to find the minimum
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0=2W-1280000/W²
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32000/(40)²=H
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