A rectangle is a parallelogram, so its opposite sides are equal. The diagonals of a rectangle are equal and bisect each other.
SAS, two sides are congruent and the angles are equal
the answer is 21 it really not it just I have to do this for this app that won't give me these for answers
(I crossed simplify)
Next cross multiply;
3b = 1
b = 1/3
To check if the statement is true just substitute the value of b in the equation;
3b = 1
3(1/3) = 1
1 = 1