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EleoNora [17]
3 years ago
9

2x+5y=-21 , -2x+3y+-27

Mathematics
1 answer:
Elis [28]3 years ago
8 0

Answer:

x=4.5 and y=  -6

Step-by-step explanation:

2x+5y= -21

-2x+3y= -27

add the two equations: 8y= -48

y=-48/8= -6

sub for y in 2x+5y= -21

2x + 5(-6)=-21, 2x-30= -21

2x= -21+30= 9

x= 9/2=4.5

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O, R and S are points in the same horizontal plane. /OR/ = 20m and /OS/= 32m.The bearing of R and S from O are 030° and 135° res
Viktor [21]
<h3>Answer:  roughly 12.6274 meters</h3>

The more accurate value is 12.6274169979696, though it's not fully exact.

Round this however you need to.

The exact distance 32*sin(45) - 10 meters.

===========================================================

Explanation:

Refer to the diagram below.

I'll use point A in place of point O since the letter 'oh' is very similar looking to the number zero.

Plot point A at the origin (0,0). While at point A, look directly north. Then turn 30 degrees eastward to look at the bearing 030°. Next, move 20 meters along that bearing direction to arrive at point R. Segment AR is 20 meters long.

In the diagram, note how angle RAB is 30 degrees. The side opposite this is BR = m.

We can use the sine ratio to say that

sin(angle) = opposite/hypotenuse

sin(A) = BR/AR

sin(30) = m/20

m = 20*sin(30)

m = 10

-----------------------------------

While still at point A, look directly north and turn 135 degrees clockwise (ie toward the east) and move 32 meters along that bearing. You'll arrive at point S as the diagram shows.

Notice how

angle RAB + angle RAC + angle CAS = 30+60+45 = 135

The remaining angle DAS is 180-135 = 45 degrees.

When focusing on triangle DAS, we can say

sin(A) = DS/AS

sin(45) = n/32

n = 32*sin(45)

n = 22.6274169979696

This value is approximate.

----------------------------------

Subtract the values of m and n

n - m = 32*sin(45) - 10 = exact distance

n - m = 22.6274169979696 - 10

n - m = 12.6274169979696

n - m = 12.6274 = approximate distance

Round it however you need to. I'm choosing to round to four decimal places.

So we see that point S is roughly 12.6274 meters east of point R.

If your teacher wants the exact distance, then stick with 32*sin(45)-10.

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3 years ago
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Answer:

The correct option is;

Corresponding angles theorem

Step-by-step explanation:

Type of lines of lines a and b = Horizontal and parallel lines

The transversal to a and b = Line c

The angles between a and c labelled clockwise from the upper left quarter segment =  1, 2, 4 and 3

The angles between b and c labelled clockwise from the upper left segment =  5, 6, 8 and 7

Therefore, we have;

Statement   {}                                                   Reason

1. a║b, c is a transversal   {}                             Given

2. ∠6 ≅ ∠2       {}                                              Corresponding angles theorem

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5. ∠2 is supp. to ∠8        {}                               Congruent supplement theorem

Corresponding angles are the angles located in spatially similar or matching corners of two lines that have been crossed by the same transversal. When the two lines having a common transversal are parallel, the corresponding angles will be congruent.                        

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V: Volume
r: radius
h: height
πr^2 = base area of a cone

Answer
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Step-by-step explanation:

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