Step-by-step explanation:
Since we have a right triangle, we use the Pythagorean Theorem
[tex] {a}^{2} + {b}^{2} = {c}^{2} [/tex]
or
[tex]c = \sqrt{ {a}^{2} + {b}^{2} } [/tex]
where a and b are the legs and c is the hypotenuse
Remember the legs are the sides that form that right angle, and the hypotenuse is the side opposite of the right angle.
So here the hypotenuse is 8, and one of the legs is 4. So we plug those values into the formula
[tex] 8 = \sqrt{ {b}^{2} + {4}^{2} } [/tex]
