The horizontal distance from Emma's house to tree house is 7 units and the vertical distance is 3 units.
Draw the horizontal and vertical lines to form a right triangle.
Label the vertices as A, B and C.
By Pythagorean theorem, [tex]AC^{2} =AB^{2}+ BC^{2}[/tex]
= [tex]3^{2} +7^{2}[/tex]
= 9 + 49
= 58
So, [tex]AC = \sqrt{58}[/tex]
Hence, distance from Emma's house to tree house is [tex]\sqrt{58}[/tex] units.
