Equations that look different but have the same solution are said to be

a. equivalent
b. expressions
c. equals
d. similar
e. radical

Let's define each choice to differentiate which is the answer

A. Equivalent - equivalent equations may not look exactly the same on face value. But they are equivalent because they have the same exact solution.

B. Expressions - expression is a general term for equations that are formed from word problems

C. Equal - equal equations are the exact duplicate of each other

D. Similar - this term is only used on geometric shapes to tell that the two shapes have a fixed ratio of their similar sides or angles

E. Radical - radical equations are those involving fractions

Therefore, from their descriptions, the answer is A.