# Angle between Lines

If the acute angle $\theta$ between two straight lines $y = m_1 x + a$ and $y = m_2 x + b$, then$$\tan{\theta} = \left|\frac{m_1 – m_2}{1+m_1 \times m_2}\right|$$ Example 1: Straight Lines in Standard Form Find the acute angles between the lines \( y = -2x + 4 […]