The friend is incorrect because 2 translations would just move the shape to a different area, then a reflection would reflect it.
Long story short: if you do to translations that only move in one direction for ex. X+10 y+ 0 then it will be a glide reflection
U will use the pemdas method which is if u check parentheses, exponents, multiplication, division, addition, subtraction. for ex. say the expression is 5 + 30+ (5x10) u will check if u have any p, e, m, d, a, or s and do those steps in order. sometimes u will read left to right if it’s a divison first and then a multiplication
Pythagorean Theorem: a^2+b^2=c^2
(9)^2 + b^2 = (23)^2
81 + b^2 = 529
b^2 = 529 - 81
b^2 = 448
b^2 =

b = 21.2