Brainliest +10 point pls help

Arley is building a model of a city map. in one part of the city, three roads form a right triangle, which harley draws as triangle abc, with the following measures: m∠b=90° and m∠a=30°. in his scale model, the hypotenuse of triangle abc, ac¯¯¯¯¯¯¯¯, has a length of 817−−√ cm. what is the value of a (the length of bc¯¯¯¯¯¯¯¯)?

Why is x= 4 a solution to the proportion 14/x 56/1 6

Heather is riding a quadratic function that represents a parabola that touches but does not cross the x-axis at x=-6