1. **Problem Statement:** Find the angle between the two lines given by the equations:
$$x + 7y - 3 = 0$$
and
$$x - y + 5 = 0$$
2. **Formula to use:** The angle $\theta$ between two lines with slopes $m_1$ and $m_2$ is given by:
$$\tan \theta = \left| \frac{m_1 - m_2}{1 + m_1 m_2} \right|$$
3. **Find the slopes of the lines:**
For the first line $x + 7y - 3 = 0$, rewrite in slope-intercept form $y = mx + c$:
$$7y = -x + 3$$
$$y = \frac{-1}{7}x + \frac{3}{7}$$
So, $m_1 = -\frac{1}{7}$.
For the second line $x - y + 5 = 0$:
$$-y = -x - 5$$
$$y = x + 5$$
So, $m_2 = 1$.
4. **Calculate $\tan \theta$:**
$$\tan \theta = \left| \frac{-\frac{1}{7} - 1}{1 + \left(-\frac{1}{7}\right)(1)} \right| = \left| \frac{-\frac{1}{7} - \frac{7}{7}}{1 - \frac{1}{7}} \right| = \left| \frac{-\frac{8}{7}}{\frac{6}{7}} \right|$$
5. **Simplify the fraction:**
$$\tan \theta = \left| \frac{\cancel{\frac{8}{7}}}{\cancel{\frac{6}{7}}} \times \frac{7}{7} \right| = \left| -\frac{8}{6} \right| = \frac{8}{6} = \frac{4}{3}$$
6. **Find the angle $\theta$:**
$$\theta = \arctan \left( \frac{4}{3} \right)$$
Using a calculator or known values:
$$\theta \approx 53.13^\circ$$
**Final answer:** The angle between the two lines is approximately $53.13^\circ$.
Angle Between Lines 9A8Fa4
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.