ANSWER
7.8cm
EXPLANATION
Given an acute angle of the right triangle to be 40°, the two sides of the triangles involve are the opposite side and the hypotenuse.
The trigonometric ratio that, involves opposite side and the hypotenuse is the sine ratio.
[tex] \sin(40 \degree) = \frac{opposite}{hypotenuse} [/tex]
[tex] \sin(40 \degree) = \frac{5}{hypotenuse} [/tex]
hypotenuse =5÷sin(40°)
hypotenuse=7.77cm
