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Pls help G, H, I, J pls explain​

Pls help G, H, I, J pls explain​-example-1
User Mauna
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2 Answers

17 votes
17 votes

Answer:

G. m∠ABD = 54°

H. m∠DBC = 126°

I. m∠XYW = 40°

J. m∠WYZ = 50°

Explanation:

∠ABD and ∠DBC are supplementary angles. This means their angles have a sum of 180°.


(1)/(2)x+20+2x-10=180\\(5)/(2)x+10=180\\(5)/(2)x=170\\x=68

m∠ABD = 1/2(68) + 20 = 34 + 20 = 54

m∠DBC = 2(68) - 10 = 136 - 10 = 126

Same concept for ∠XYW and ∠WYZ only this time they are complementary angles. This means their angles have a sum of 90°.


1(1)/(4)x-10+(3)/(4)x+20=90\\2x+10=90\\2x=80\\x=40

m∠XYW = 1 1/4(40) - 10 = 50 - 10 = 40

m∠WYZ = 3/4(40) + 20 = 30 + 20 = 50

User Esta
by
2.9k points
18 votes
18 votes

Part G

The two angles ABD and DBC form a straight line, so the angles add to 180 degrees.

Let's solve for x.

angle ABD + angle DBC = 180

(0.5x+20) + (2x-10) = 180

2.5x+10 = 180

2.5x = 180-10

2.5x = 170

x = 170/2.5

x = 68

Then we'll use this to find angle ABD

angle ABD = 0.5*x + 20

angle ABD = 0.5*68 + 20

angle ABD = 34 + 20

angle ABD = 54

Answer: 54 degrees

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Part H

Use the value of x we found back in part G to find the measure of angle DBC

angle DBC = 2x - 10

angle DBC = 2(68) - 10

angle DBC = 136 - 10

angle DBC = 126

An alternative is to subtract the measure of angle ABD from 180

angle ABD + angle DBC = 180

angle DBC = 180 - (angle ABD)

angle DBC = 180 - 54

angle DBC = 126

Answer: 126 degrees

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Part I

This time, the two angles add to 90 degrees as shown by the square corner marker.

(angle XYW) + (angle WYZ) = 90

(1.25x - 10) + (0.75x + 20) = 90

2x + 10 = 90

2x = 90-10

2x = 80

x = 80/2

x = 40

which then leads to,

angle XYW = 1.25*x - 10

angle XYW = 1.25*40 - 10

angle XYW = 50 - 10

angle XYW = 40

Answer: 40 degrees

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Part J

We can subtract the result of part I from 90 degrees to get the answer

angle WYZ = 90 - (angle XYW)

angle WYZ = 90 - 40

angle WYZ = 50

Or we could plug the x value x = 40 into the expression for angle WYZ

angle WYZ = 0.75*x + 20

angle WYZ = 0.75*40 + 20

angle WYZ = 30 + 20

angle WYZ = 50

Answer: 50 degrees

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Summary:

The answers we found were

  • G. 54 degrees
  • H. 126 degrees
  • I. 40 degrees
  • J. 50 degrees
User Alex Morozov
by
3.0k points