A triangle has coordinates A(-2,-1), B(-1,2), and c(1.-2). If the triangle is reflected across the y-axis, what are the new coordinates of the triangle?

Can any one me with the answers to these questions asap?

In right ∆abc shown below, the midpoint of hypotenuse ac is located at d and segment bd is drawn.if ab = 12 and bc = 16, then explain why bd = 10. hint: consider what you know about the diagonals of a rectangle.

What effect would doubling all the dimensions of a triangular pyramid have on the volume of the pyramid? explain your reasoning.