Answer :

To determine whether there are zero, one, or two triangles possible with the given values [tex]\( m\angle A = 48^\circ \)[/tex], [tex]\( a = 10 \)[/tex] m, and [tex]\( b = 12 \)[/tex] m, we follow these steps:

1. Determine the relationship of the sides and the sine of angle [tex]\( A \)[/tex]:
Using the Law of Sines:
[tex]\[ \frac{\sin(A)}{a} = \frac{\sin(B)}{b} \][/tex]
Plug in the given values:
[tex]\[ \frac{\sin(48^\circ)}{10} = \frac{\sin(B)}{12} \][/tex]

2. Calculate [tex]\(\sin(48^\circ)\)[/tex]:
[tex]\[ \sin(48^\circ) \approx 0.7431 \][/tex]
So, the equation becomes:
[tex]\[ \frac{0.7431}{10} = \frac{\sin(B)}{12} \][/tex]

3. Solve for [tex]\(\sin(B)\)[/tex]:
[tex]\[ \sin(B) = 12 \times \frac{0.7431}{10} = 12 \times 0.07431 = 0.89172 \][/tex]

4. Check if [tex]\(\sin(B)\)[/tex] is within the valid range for sine values (0 to 1):
Since [tex]\( \sin(B) = 0.89172 \)[/tex] which is within [tex]\([0, 1]\)[/tex], we can find angle [tex]\( B \)[/tex].

5. Find angle [tex]\( B \)[/tex]:
Using the arcsine function:
[tex]\[ B = \arcsin(0.89172) \approx 63.1^\circ \][/tex]

6. Calculate the third angle [tex]\( C \)[/tex]:
Use the fact that the sum of angles in a triangle is [tex]\( 180^\circ \)[/tex]:
[tex]\[ C = 180^\circ - A - B = 180^\circ - 48^\circ - 63.1^\circ = 68.9^\circ \][/tex]

7. Consider the possibility of a second triangle:
In the case of the ambiguous case (SSA condition), angle [tex]\( B \)[/tex] could potentially have a second solution since [tex]\(\sin(B) = \sin(180^\circ - B)\)[/tex]:
[tex]\[ B_2 = 180^\circ - 63.1^\circ = 116.9^\circ \][/tex]
Check the corresponding third angle [tex]\( C_2 \)[/tex]:
[tex]\[ C_2 = 180^\circ - A - B_2 = 180^\circ - 48^\circ - 116.9^\circ = 15.1^\circ \][/tex]

8. Validate the second set of angles:
Both [tex]\( B_2 = 116.9^\circ \)[/tex] and [tex]\( C_2 = 15.1^\circ \)[/tex] are valid angles, meaning the second set of angles does form a triangle.

Hence, there are two possible triangles that can be formed with the given values.

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