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yanalaym [24]
2 years ago
13

Answer the following questions about pencil drawing: - When were pencils first used? - What is graphite? - What is an HB pencil?

- What happens when the H.
SAT
1 answer:
pochemuha2 years ago
4 0
-Pencils were first used in 1662.
-Graphite is a crystalline form of the element carbon with its atoms arranged in a hexagonal structure.
- HB is a graphite hardness/grading scale: the higher the number next to H, the harder and lighter/less dark the pencil lead is.
- The H stands for “hard.”
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Altitudes $\overline{ad}$ and $\overline{be}$ of acute triangle $abc$ intersect at point $h$. if $\angle ahb = 128^\circ$ and $\
DENIUS [597]

The Angle HCA is equal to 52°. This is arrived at using the knowledge of the Total value of Angles in a Triangle and the Total Value of Angles in a Polygon.

<h3>What other principles were used to arrive at the answer?</h3>

The other principles of mathematics that were used to arrive at the above answer are:

  • Total Angles on a straight line;
  • Total Angles on a point; and
  • Line segments.

<h3>What are the Steps to the Solution? </h3>

Step 1 - Recall that we have been given Angles AHB and BAH to be 128° and 28° respectively.

We also know that:

  1. The sum of angles in a triangle is 180°;...................A
  2. The sum of angles on a straight line is 180°;.........B
  3. The sum of angles in a polygon is 360°; while.....C
  4. The total sum of angles at a point is 360°.............D

Since A...therefore:

When ∠AHB (128°) and ∠BAH are taken from 180° we have DBA = ∠28°.

By observation, we can deduce that ∠BDE, ∠CDH, ∠CEH and ∠AEH are all right-angled triangles.


Using the above, we are able to repeat this process of solving for each angle until we have ∠HCA.

To verify that our answer is correct, recall that sum of angles in a polygon is 360°

That means:

∠BDA + ∠DHE + ∠CEH + ∠HCA = 360°

That is, 90+ 128 + 90 + 52 = 360°

See attached images and;

Learn more about Angles in a Triangle at:
brainly.com/question/25215131
#SPJ1

8 0
2 years ago
If Erica walks 4 miles in 60 minutes, then Erica will walk how far in 100 minutes if she walks at the
Diano4ka-milaya [45]
Divide 60/4 = 15
100/15 = 6.666 which rounds to 6.67 or that rounds to 6.7
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3 years ago
Which statements about the system are true? select two options. Y = y equals startfraction 1 over 3 endfraction x minus 4. X – 4
Shtirlitz [24]

Answer:

x-43y-x=-7

or, x-x-43y=-7

or, 43y=-7

or, y =-7-43

or, y=50

8 0
2 years ago
Banks use debit-to-income ratios in order to:
erma4kov [3.2K]
The answer is D. Analyse the value of a borrowers home and cars to be used as collateral for a loan.
7 0
3 years ago
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Pls help major test so no guessing☺️☺️
aleksklad [387]

Answer:

3 1/4

Explanation:

closer to the 3 equaling a 1/4

6 0
2 years ago
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