Question

The ladder must be placed 3 feet from a wall. The ladder is 12 feet long how far above the ground dose the ladder touch the wall

Answer 1

${a}^{2} + {3}^{2} = {12}^{2} \\ {a}^{2} + 9 = 144 \\ {a}^{2} = 144 - 9 \\ {a}^{2} =135 \\ \sqrt{ {a}^{2} } = \sqrt{135} \\ a = 11.619$
the top of ladder is approximately 11.6 ft. above the ground.