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UNO [17]
3 years ago
9

−3x − 8y = 20 −5x + y = 19 solved by substitution

Mathematics
2 answers:
beks73 [17]3 years ago
7 0

Delete as this is the wrong answer. Made a typo in the answer.

Answer:

x = \frac{-212}{3}

y = 24

Step-by-step explanation:

-3x - 8y = 20  .... (1)

-5x + y = 19   .... (2)

What we can do is take the (2) equation

-5x + y = 19

and solve for y by adding 5x to both sides

y = 24

now that we have y we substitute it in for y in equation (1)

-3x - 8(24) = 20

-3x - 192 = 20

we want to solve for x so we need to get its self.

add 192 to both sides

-3x = 212

now we divide both sides by -3. It's going to be a fraction.

x = \frac{-212}{3}

polet [3.4K]3 years ago
6 0

Answer:

x=-4

y=-1

Step-by-step explanation:

-3x-8y=20

-5x+y=19

rewrite for y:

y=19+5x

substitute y

-3x-8(19+5x)=20

-3x-152-40x=20

-3x-152-40x+152=20+152

-43x=172

-43x/-43=172/-43

x=-4

substitute x

-5(-4)+y=19

20+y=19

y=-1

check:

-3(-4)-8(-1)=20

12+8=20

-5(-4)+-1=19

20-1=19

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The hypotenuse of right triangle ABC, line segment AC, measures 13 cm. The length of line segment BC is 5 cm.
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Answer:

The approximate difference between m∠C and m∠A is 45° to the nearest degree

Step-by-step explanation:

* Lets talk about the right triangle

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∵ m∠B = 90°

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∴ m∠A + m∠C = 180° - 90° = 90°

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∵ BC is the opposite side of angle A

∴ sin A = BC/AC

∵ BC = 5 cm

∵ AC = 13 cm

∴ sin A = 5/13

- Lets find m∠∠A by using sin ^-1

∴ m∠A = sin^{-1}\frac{5}{13}=22.62

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∵ m∠A + m∠C = 90°

∴ 22.62° + m∠C = 90 ⇒ subtract 22.62 from both sides

∴ m∠C = 67.38°

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∴ The approximate difference between m∠C and m∠A is:

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Answer:

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mario62 [17]

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Y=0.006x^3 -0.06x^2+1.4x, x is horizontal, and y is vertical, is it possible for the vertical distance of the helicopter to be t
Lera25 [3.4K]

Answer:

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Step-by-step explanation:

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