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3 years ago

Solve the system using elimination. 3x + 3y = –9 3x – 3y = 21

Mathematics

1 answer:

scoundrel [369]3 years ago

6 0

Answer:

y=-5,x=2

Step-by-step explanation:

3x+3y=-9________________eqn 1

3x-3y=21________________eqn 2

using elimination method

3x+3y=-9

3x-3y=21

subtract equation 2 from equation 1

0+6y=-30

6y=-30

y=-30/6

y=-5

substitute the value of y in equation 1

3x+3y=-9

3x+3(-5)=-9

3x-15=-9

3x=-9+15

3x=6

x=6/3

x=2

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sp2606 [1]

Answer:

$3.50

Step-by-step explanation:

Store X:

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3 years ago

vitfil [10]

Answer:

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Step-by-step explanation:

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2 years ago

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Answer:

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Step-by-step explanation:

8 0

2 years ago

Please help me I give a lot thanks

inna [77]

Answer:

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Step-by-step explanation:

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3 years ago

Beverly is driving up a hill at an incline of 45 degrees. She will travel 13 miles to reach the top. What is the height of the h

quester [9]

Answer:

The height of the hill is of 9.19 miles.

Step-by-step explanation:

Relations in a right triangle:

The sine of an angle is given by the measure of the opposite side divided by the hypotenuse.

The cosine of an angle is given by the measure of the adjacent side divided by the hypotenuse.

In this question:

Angle of 45º, and drives 13 miles. Due to the inclination, this represents the hypotenuse.

The height is the opposite side. So

$\sin{45} = \frac{h}{13}$

We have that $\sin{45} = \frac{\sqrt{2}}{2} = 0.71$

$\sin{45} = \frac{h}{13}$

$0.71 = \frac{h}{13}$

$h = 13*0.71 = 9.19$

The height of the hill is of 9.19 miles.

3 0

3 years ago