2.) Find the circumference of a circle if the area of the circle is 379.94 in? Use 3.14 as an approximation for pi

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

Aline is perpendicular to another line m2= (-1/m1), where m1 is the slope of the original line and m2 is the slope of the perpendicular line. which of the following equations represents the line that passes through the point (-2,1) and is perpendicular to the line below?

Quadrilateral ghij has coordinates g(5, 1), h(4, -3), i(6, -1), and j(2, 1). if the quadrilateral is reflected over the line y = x, what are the coordinates of h'?