Questions: Find the values of (x, y), and (z) in the figure (in degrees), where (b=2) and (c=14).
Step 1
Recall that in a triangle, the sum of the measures of an exterior angle and its adjacent angle is 180,180. and the sum of the measures of the internal angles is (180^circ).
Using the above facts and the given figure, write the system of linear equations.
[
left
beginarrayrlrl
x+y+z =180 textEquation 1
x+1.5 z+2 =180
y+1.5 z-14 =180
endarray, quad
beginarrayll
180
endarray
right.
]
Step 2
Rewrite the system in standard form.
[
left
beginarrayl
x+y+z=180
x+1.5 z=
y+1.5 z=194
endarray
right.
]
Adding -1 times the second equation to the first equation produces a new first equation.
[
left
beginarrayl
y-0.5 z=
x+1.5 z=
y+1.5 z=194
endarray
right.
]
Transcript text: Find the values of $x, y$, and $z$ in the figure (in degrees), where $b=2$ and $c=14$.
Step 1
Recall that in a triangle, the sum of the measures of an exterior angle and its adjacent angle is 180,180 . and the sum of the measures of the internal angles is $180^{\circ}$.
Using the above facts and the given figure, write the system of linear equations.
\[
\left\{\begin{array}{rlrl}
x+y+z & =180 & & \text { Equation 1 } \\
x+1.5 z+2 & =180 \\
y+1.5 z-14 & =180
\end{array}, \quad \begin{array}{ll}
180
\end{array}\right.
\]
Step 2
Rewrite the system in standard form.
\[
\left\{\begin{array}{l}
x+y+z=180 \\
x+1.5 z=\square \\
y+1.5 z=194
\end{array}\right.
\]
Adding -1 times the second equation to the first equation produces a new first equation.
\[
\left\{\begin{array}{l}
y-0.5 z=\square \\
x+1.5 z=\square \\
y+1.5 z=194
\end{array}\right.
\]
Solution
Solution Steps
Step 1: Write the system of linear equations
Using the given information and the properties of triangles, we can write the following system of linear equations:
\( x + y + z = 180 \) (sum of internal angles in a triangle)
\( x + 1.5z = 180 \) (sum of an exterior angle and its adjacent interior angle)
\( y + 1.5z - 14 = 180 \) (sum of an exterior angle and its adjacent interior angle)
Step 2: Simplify the equations
Rewrite the equations in standard form:
\( x + y + z = 180 \)
\( x + 1.5z = 180 \)
\( y + 1.5z = 194 \) (simplified from \( y + 1.5z - 14 = 180 \))
Step 3: Solve the system of equations
Subtract the second equation from the first:
\[ (x + y + z) - (x + 1.5z) = 180 - 180 \]
\[ y - 0.5z = 0 \]
\[ y = 0.5z \]
Substitute \( y = 0.5z \) into the third equation:
\[ 0.5z + 1.5z = 194 \]
\[ 2z = 194 \]
\[ z = 97 \]
Substitute \( z = 97 \) back into \( y = 0.5z \):
\[ y = 0.5 \times 97 \]
\[ y = 48.5 \]
Substitute \( y = 48.5 \) and \( z = 97 \) into the first equation:
\[ x + 48.5 + 97 = 180 \]
\[ x + 145.5 = 180 \]
\[ x = 34.5 \]
Final Answer
The values of \( x \), \( y \), and \( z \) are:
\[ x = 34.5^\circ \]
\[ y = 48.5^\circ \]
\[ z = 97^\circ \]