Letter a represents a plane and letter b represents a plane. how far apart are the airplanes

The roots of the function f(x) = x2 – 2x – 3 are shown. what is the missing number?

Plz ( true - false) all triangles have interior angles whose measure sum to 90.

"which statement is necessarily true if bd is an altitude to the hypotenuse of right ? abc? a.) ? adb? ? bdc b.) ? adb~? bdc c.) abbc=acbd d.) ? bac? ? bdc"