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3 years ago

Solve the system of equations below. A. B. C. D.

Mathematics

1 answer:

timofeeve [1]3 years ago

7 0

Answer:

A. (-7 -2)

Step-by-step explanation:

You can eliminate y by multiplying the first equation by 7 and subtracting 6 times the second equation:

7(-3x +6y) -6(5x +7y) = 7(9) -6(-49)

-21x +42y -30x -42y = 63 +294 . . . . eliminate parentheses

-51x = 357 . . . . . . . . collect terms

x = -7 . . . . . . . divide by -51. This matches answer choice A.

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What addition doubles fact can help you find 4+ 3? Explain how you know

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3 years ago

A quality control expert found 12 defective cell phones in a shipment of 75 cell phones, based on these results how many cell ph

mart [117]

Answer:

240 cell phones

Step-by-step explanation:

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3 years ago

A right square pyramid with base edges of length $8\sqrt{2}$ units each and slant edges of length 10 units each is cut by a plan

seropon [69]

Answer:

32 $unit^{3}$

Step-by-step explanation:

Given:

The slant length 10 units
A right square pyramid with base edges of length 8 $\sqrt{2}$

Now we use Pythagoras to get the slant height in the middle of each triangle:

$\sqrt{10^{2 - (4\sqrt{2} ^{2} }) }$ = $\sqrt{100 - 32}$ = $\sqrt{68}$ units

One again, you can use Pythagoras again to get the perpendicular height of the entire pyramid.

$\sqrt{68-(4\sqrt{2} ^{2} )}$ = $\sqrt{68 - 32}$ = 6 units.

Because slant edges of length 10 units each is cut by a plane that is parallel to its base and 3 units above its base. So we have the other dementions of the small right square pyramid:

The height 3 units
A right square pyramid with base edges of length 4 $\sqrt{2}$

So the volume of it is:

V = 1/3 *3* 4 $\sqrt{2}$

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5 0

4 years ago

Four times the sum of 8 and some number is 4. What is the number?

Lunna [17]

Answer:

$\Huge \boxed{\mathrm{-7}}$

$\rule[225]{225}{2}$

Step-by-step explanation:

Let the number be x.

$4(x+8)=4$

Dividing both sides by 4,

$x+8=1$

Subtracting 8 from both sides,

$x=-7$

The number is -7.

$\rule[225]{225}{2}$

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3 years ago

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Solve the system of equations algebraically. Verify your answer using the graph.

nirvana33 [79]

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6 0

3 years ago

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