diff --git a/poincare/Makefile b/poincare/Makefile
index 4cb4a16cb..128627af7 100644
--- a/poincare/Makefile
+++ b/poincare/Makefile
@@ -102,7 +102,7 @@ tests += $(addprefix poincare/test/,\
   simplify_easy.cpp\
 )
 
-tests_orig += $(addprefix poincare/test/,\
+tests += $(addprefix poincare/test/,\
   addition.cpp\
   complex.cpp\
   division.cpp\
diff --git a/poincare/test/helper.cpp b/poincare/test/helper.cpp
index cde1e0cd7..b3dc2944d 100644
--- a/poincare/test/helper.cpp
+++ b/poincare/test/helper.cpp
@@ -32,16 +32,6 @@ void assert_parsed_expression_type(const char * expression, Poincare::Expression
   delete e;
 }
 
-void assert_parsed_simplified_expression_type(const char * expression, Poincare::Expression::Type type) {
-  Expression * e = parse_expression(expression);
-  e->simplify();
-  //Expression * e2 = e->simplify();
-  //assert(e2);
-  assert(e->type() == type);
-  delete e;
-  //delete e2;
-}
-
 template<typename T>
 void assert_parsed_expression_evaluates_to(const char * expression, Complex<T> * results, int numberOfRows, int numberOfColumns, Expression::AngleUnit angleUnit) {
   GlobalContext globalContext;
diff --git a/poincare/test/helper.h b/poincare/test/helper.h
index 39d3376f3..4e0e37c4e 100644
--- a/poincare/test/helper.h
+++ b/poincare/test/helper.h
@@ -4,7 +4,6 @@ constexpr Poincare::Expression::AngleUnit Degree = Poincare::Expression::AngleUn
 constexpr Poincare::Expression::AngleUnit Radian = Poincare::Expression::AngleUnit::Radian;
 
 void assert_parsed_expression_type(const char * expression, Poincare::Expression::Type type);
-void assert_parsed_simplified_expression_type(const char * expression, Poincare::Expression::Type type);
 template<typename T>
 void assert_parsed_expression_evaluates_to(const char * expression, Poincare::Complex<T> * results, int numberOfRows, int numberOfColumns = 1, Poincare::Expression::AngleUnit angleUnit = Degree);
 template<typename T>
diff --git a/poincare/test/identity.cpp b/poincare/test/identity.cpp
index e187512d5..1b3906360 100644
--- a/poincare/test/identity.cpp
+++ b/poincare/test/identity.cpp
@@ -29,8 +29,8 @@ QUIZ_CASE(poincare_identity_simple_term) {
 }
 
 QUIZ_CASE(poincare_identity_commutativity) {
-  assert(identical_to("1+2", "2+1"));
+  assert(equivalent_to("1+2", "2+1"));
   //assert(identical_to("1*2", "2*1"));
-  assert(!identical_to("1-2", "2-1"));
-  assert(!identical_to("1/2", "2/1"));
+  assert(!equivalent_to("1-2", "2-1"));
+  assert(!equivalent_to("1/2", "2/1"));
 }
diff --git a/poincare/test/simplify_utils.cpp b/poincare/test/simplify_utils.cpp
index d26ffd067..c837bb981 100644
--- a/poincare/test/simplify_utils.cpp
+++ b/poincare/test/simplify_utils.cpp
@@ -21,11 +21,10 @@ bool simplifies_to(const char * input_string, const char * expected_string) {
   print_expression(input);
 #endif
 
-  Expression * simplified = input->simplify();
-  assert(simplified != nullptr);
+  Expression::simplify(&input);
 #if POINCARE_TESTS_PRINT_EXPRESSIONS
   cout << "Simplified = " << endl;
-  print_expression(simplified);
+  print_expression(input);
 #endif
 
   Expression * expected = Expression::parse(expected_string);
@@ -35,10 +34,9 @@ bool simplifies_to(const char * input_string, const char * expected_string) {
   print_expression(expected);
 #endif
 
-  bool isIdentical = simplified->isIdenticalTo(expected);
+  bool isIdentical = input->compareTo(expected) == 0;
 
   delete expected;
-  delete simplified;
   delete input;
 
   return isIdentical;
@@ -63,7 +61,7 @@ bool identical_to(const char * input_string, const char * expected_string) {
   print_expression(expected);
 #endif
 
-  bool isIdentical = input->isIdenticalTo(expected);
+  bool isIdentical = input->compareTo(expected) == 0;
 
   delete expected;
   delete input;
@@ -90,25 +88,21 @@ bool equivalent_to(const char * input_string, const char * expected_string) {
   print_expression(expected);
 #endif
 
-  Expression * simplified_input = input->simplify();
-  assert(simplified_input != nullptr);
+  Expression::simplify(&input);
 #if POINCARE_TESTS_PRINT_EXPRESSIONS
   cout << "Simplified Input = " << endl;
-  print_expression(simplified_input);
+  print_expression(input);
 #endif
 
-  Expression * simplified_expected = Expression::parse(expected_string);
-  assert(simplified_expected != nullptr);
+  Expression::simplify(&expected);
 #if POINCARE_TESTS_PRINT_EXPRESSIONS
   cout << "Simplified Expected = " << endl;
-  print_expression(simplified_expected);
+  print_expression(expected);
 #endif
-  bool isEquivalent = simplified_input->isIdenticalTo(simplified_expected);
+  bool isEquivalent = input->compareTo(expected) == 0;
 
   delete expected;
   delete input;
-  delete simplified_expected;
-  delete simplified_input;
 
   return isEquivalent;
 }
diff --git a/poincare/test/simplify_utils.h b/poincare/test/simplify_utils.h
index 28dd36297..98805b49e 100644
--- a/poincare/test/simplify_utils.h
+++ b/poincare/test/simplify_utils.h
@@ -6,6 +6,8 @@ bool simplifies_to(const char * input_string, const char * expected_string);
 
 /* Tests that the first expression is identical to the second. */
 bool identical_to(const char * input_string, const char * expected_string);
+
+/* Tests that the first and the second expressions simplify to the same expression. */
 bool equivalent_to(const char * input_string, const char * expected_string);
 
 #endif // POINCARE_TEST_SIMPLIFY_UTILS_H
diff --git a/poincare/test/trigo.cpp b/poincare/test/trigo.cpp
index 24f146bb8..0ba08252e 100644
--- a/poincare/test/trigo.cpp
+++ b/poincare/test/trigo.cpp
@@ -7,18 +7,18 @@
 using namespace Poincare;
 
 QUIZ_CASE(poincare_parse_trigo) {
-  assert_parsed_simplified_expression_type("sin(0)", Expression::Type::Sine);
-  assert_parsed_simplified_expression_type("cos(0)", Expression::Type::Cosine);
-  assert_parsed_simplified_expression_type("tan(0)", Expression::Type::Tangent);
-  assert_parsed_simplified_expression_type("cosh(0)", Expression::Type::HyperbolicCosine);
-  assert_parsed_simplified_expression_type("sinh(0)", Expression::Type::HyperbolicSine);
-  assert_parsed_simplified_expression_type("tanh(0)", Expression::Type::HyperbolicTangent);
-  assert_parsed_simplified_expression_type("acos(0)", Expression::Type::ArcCosine);
-  assert_parsed_simplified_expression_type("asin(0)", Expression::Type::ArcSine);
-  assert_parsed_simplified_expression_type("atan(0)", Expression::Type::ArcTangent);
-  assert_parsed_simplified_expression_type("acosh(0)", Expression::Type::HyperbolicArcCosine);
-  assert_parsed_simplified_expression_type("asinh(0)", Expression::Type::HyperbolicArcSine);
-  assert_parsed_simplified_expression_type("atanh(0)", Expression::Type::HyperbolicArcTangent);
+  assert_parsed_expression_type("sin(0)", Expression::Type::Sine);
+  assert_parsed_expression_type("cos(0)", Expression::Type::Cosine);
+  assert_parsed_expression_type("tan(0)", Expression::Type::Tangent);
+  assert_parsed_expression_type("cosh(0)", Expression::Type::HyperbolicCosine);
+  assert_parsed_expression_type("sinh(0)", Expression::Type::HyperbolicSine);
+  assert_parsed_expression_type("tanh(0)", Expression::Type::HyperbolicTangent);
+  assert_parsed_expression_type("acos(0)", Expression::Type::ArcCosine);
+  assert_parsed_expression_type("asin(0)", Expression::Type::ArcSine);
+  assert_parsed_expression_type("atan(0)", Expression::Type::ArcTangent);
+  assert_parsed_expression_type("acosh(0)", Expression::Type::HyperbolicArcCosine);
+  assert_parsed_expression_type("asinh(0)", Expression::Type::HyperbolicArcSine);
+  assert_parsed_expression_type("atanh(0)", Expression::Type::HyperbolicArcTangent);
 }
 
 QUIZ_CASE(poincare_trigo_evaluate) {