Mathematics

Problem

7\,\text{m}

long ladder leans against a vertical wall, making an angle of

45^{\circ}

with the ground. How far up the wall does the ladder touch? a)

7\sqrt{2}\,\text{m}

7\,\text{m}

\dfrac{7\sqrt{2}}{2}\,\text{m}

\dfrac{7}{2}\,\text{m}