Questions: In triangle ABC, if m angle A is thirteen less than m angle C and m angle B is eleven less than four times m angle C, find the measure of each angle.
m angle A=
m angle B=
m angle C=
Transcript text: In $\triangle ABC$, if $m \angle A$ is thirteen less than $m \angle C$ and $m \angle B$ is eleven less than four times $m \angle C$, find the measure of each angle.
\[
\begin{array}{l}
m \angle A= \\
m \angle B= \\
m \angle C=
\end{array}
\]
Solution
Solution Steps
Step 1: Define the variables
Let \( m \angle C = x \). Then:
\( m \angle A = x - 13 \) (since \( m \angle A \) is thirteen less than \( m \angle C \)).
\( m \angle B = 4x - 11 \) (since \( m \angle B \) is eleven less than four times \( m \angle C \)).
Step 2: Use the triangle angle sum property
In any triangle, the sum of the interior angles is \( 180^\circ \). Therefore:
\[
m \angle A + m \angle B + m \angle C = 180^\circ
\]
Substitute the expressions for \( m \angle A \), \( m \angle B \), and \( m \angle C \):
\[
(x - 13) + (4x - 11) + x = 180
\]
Step 3: Simplify and solve for \( x \)
Combine like terms:
\[
x - 13 + 4x - 11 + x = 180
\]
\[
6x - 24 = 180
\]
Add \( 24 \) to both sides:
\[
6x = 204
\]
Divide both sides by \( 6 \):
\[
x = 34
\]
Step 4: Find the measures of the angles
\( m \angle C = x = 34^\circ \).
\( m \angle A = x - 13 = 34 - 13 = 21^\circ \).
\( m \angle B = 4x - 11 = 4(34) - 11 = 136 - 11 = 125^\circ \).
Final Answer
\[
\boxed{
\begin{array}{l}
m \angle A = 21^\circ \\
m \angle B = 125^\circ \\
m \angle C = 34^\circ
\end{array}
}
\]