What is the name of each variable ? Please help!!

Which expressions are equivalent to the one below? check all that apply. 25x/5x a. 5x b. 5 c. 5x•5x/5x d. 25x e. (25/5)^x f. (25-5)^x

What is the equation of the following graph in vertex form? parabolic function going down from the left through the point zero comma twelve and through the point two comma zero and turning at the point four comma negative four and going up through the point six comma zero and continuing towards infinity courtesy of texas instruments a: y = (x − 4)2 − 4 b: y = (x + 4)2 − 4 c: y = (x + 2)2 + 6 d: y = (x + 2)2 + 12

1. are the triangles similar and if so why? what is the value of x? show your work.