How many positive four-digit integer palindromes have 12 as the sum of the digits of the number?

Rhombus adef is inscribed into a triangle abc so that they share angle a and the vertex e lies on the side bc . what is the length of the side of the rhombus if ab=c, and ac=b.

Square a has a side length of (2x-7) and square b has a side length of (-4x+18). how much bigger is the perimeter of square b than square a?and show all work! you so

Acircle has a radius of 12.6cm what is the exact length of an arc formed by a central angle measuring 120