Please answer it in two minutes

State the number of possible triangles that can be formed using the given measurements.

romanna [79]

Answer: 39) 1 40) 2

41) 1 42) 0

<u>Step-by-step explanation:</u>

39) ∠A = ? ∠B = ? ∠C = 129°

a = ? b = 15 c = 45

Use Law of Sines to find ∠B:

$\dfrac{\sin B}{b}=\dfrac{\sin C}{c} \rightarrow\quad \dfrac{\sin B}{15}=\dfrac{\sin 129}{45}\rightarrow \quad \angle B=15^o\quad or \quad \angle B=165^o$

If ∠B = 15°, then ∠A = 180° - (15° + 129°) = 36°

If ∠B = 165°, then ∠A = 180° - (165° + 129°) = -114°

Since ∠A cannot be negative then ∠B ≠ 165°

∠A = 36° ∠B = 15° ∠C = 129° is the only valid solution.

40) ∠A = 16° ∠B = ? ∠C = ?

a = 15 b = ? c = 19

Use Law of Sines to find ∠C:

$\dfrac{\sin A}{a}=\dfrac{\sin C}{c} \rightarrow\quad \dfrac{\sin 16}{15}=\dfrac{\sin C}{19}\rightarrow \quad \angle C=20^o\quad or \quad \angle C=160^o$

If ∠C = 20°, then ∠B = 180° - (16° + 20°) = 144°

If ∠C = 160°, then ∠B = 180° - (16° + 160°) = 4°

Both result with ∠B as a positive number so both are valid solutions.

Solution 1: ∠A = 16° ∠B = 144° ∠C = 20°

Solution 2: ∠A = 16° ∠B = 4° ∠C = 160°

41) ∠A = ? ∠B = 75° ∠C = ?

a = 7 b = 30 c = ?

Use Law of Sines to find ∠A:

$\dfrac{\sin A}{a}=\dfrac{\sin B}{b} \rightarrow\quad \dfrac{\sin A}{7}=\dfrac{\sin 75}{30}\rightarrow \quad \angle A=13^o\quad or \quad \angle A=167^o$

If ∠A = 13°, then ∠C = 180° - (13° + 75°) = 92°

If ∠A = 167°, then ∠C = 180° - (167° + 75°) = -62°

Since ∠C cannot be negative then ∠A ≠ 167°

∠A = 13° ∠B = 75° ∠C = 92° is the only valid solution.

42) ∠A = ? ∠B = 119° ∠C = ?

a = 34 b = 34 c = ?

Use Law of Sines to find ∠A:

$\dfrac{\sin A}{a}=\dfrac{\sin B}{b} \rightarrow\quad \dfrac{\sin A}{34}=\dfrac{\sin 119}{34}\rightarrow \quad \angle A=61^o\quad or \quad \angle A=119^o$

If ∠A = 61°, then ∠C = 180° - (61° + 119°) = 0°

If ∠A = 119°, then ∠C = 180° - (119° + 119°) = -58°

Since ∠C cannot be zero or negative then ∠A ≠ 61° and ∠A ≠ 119°

There are no valid solutions.

6 0

3 years ago

In the figure M ab =45 and M cd= 23 what is the value of x?

const2013 [10]

Answer:

34°

Step-by-step explanation:

The measure of vertical angles formed by two chords is equal to one half the sum the measures of the arcs.

In other words, x is the average:

x = (23° + 45°) / 2

x = 34°

5 0

4 years ago

#3 is the tough one for me I get it but I don't can you help me and tell me how you got that answer as soon as possible.

Bas_tet [7]

1) 2 minutes = 2 x 60 = 120 seconds
2) 1500 meters per second x 120 seconds = 180 000 meters = 180 km

7 0

3 years ago

Read 2 more answers

A new car is purchased for 23700 dollars. The value of the car depreciates at 13% per year. To the nearest year, how long will i

Lyrx [107]

Answer:

9 years

Step-by-step explanation:

A new car is purchased for 23700 dollars. The value of the car depreciates at 13% per year. To the nearest year, how long will it be until the value of the car is 8000 dollars

8 0

3 years ago

Quadrilateral ABCD is transformed to create A′B′C′D′. Match the coordinates of A′ with the transformations that create it.

bulgar [2K]

Answer:

The answer is below

Step-by-step explanation:

From the image attached, the coordinates of point A is at (2, -4).

Transformation is the movement of a point from its initial location to a new position. Types of transformation include dilation, reflection, translation and rotation.

If a point A(x, y) is reflected over the x axis, the new point is at A'(x, -y)

If a point A(x, y) is translated a units right and b units down, the new location is at A'(x + a, y - b)

If a point A(x, y) is dilated by factor of a, the new location is at A'(ax, ay)

If a point A(x, y) is rotated 180° clockwise about the origin, the new location is at A'(-x, -y)

Hence:

For Quadrilateral ABCD is reflected over the x-axis, the coordinates of A' is at A'(2, 4)

For Quadrilateral ABCD is translated 2 units right and 1 unit down, the coordinates of A' is at A'(4, -5)

For Quadrilateral ABCD is dilated by a scale factor of 3, the coordinates of A' is at A'(6, -12)

For Quadrilateral ABCD is rotated 180° clockwise about the origin the coordinates of A' is at A'(-2, 4).

Step-by-step explanation:

6 0

3 years ago