The perimeter of an equilateral triangle is 26 centimeters. find the altitude of the triangle

Which composition of similarity transformations maps polygon abcd to polygon a'b'c'd'? a dilation with a scale factor less than 1 and then a reflection a dilation with a scale factor less than 1 and then a translation a dilation with a scale factor greater than 1 and then a reflection a dilation with a scale factor greater than 1 and then a translation

Can you me find the missing length. i attached an image.

Ntriangle abc, m∠a = 35° and m∠b = 40°, and a=9. which equation should you solve to find b?