diff --git a/Algebra.js b/Algebra.js
index cec0b8d..8913d49 100644
--- a/Algebra.js
+++ b/Algebra.js
@@ -714,8 +714,9 @@ if((typeof module) !== 'undefined') {
         //then add the minus one to that factor and return.
         if(s.equals(-1) && this.length > 0) {
             var fo = core.Utils.firstObject(this.factors, null, true);
-            this.add(_.symfunction(core.Settings.PARENTHESIS, [fo.obj]).negate());
+            let newObj = _.symfunction(core.Settings.PARENTHESIS, [fo.obj]).negate();
             delete this.factors[fo.key];
+            this.add(newObj);
             this.length--;
             return this;
         }
diff --git a/spec/test.js b/spec/test.js
index ff18def..4887102 100644
--- a/spec/test.js
+++ b/spec/test.js
@@ -20,9 +20,14 @@ console.global = {tsDebugChannels: {notimeout: true}};
 // const sol = nerdamer.solveEquations(testEq, [...testUnkwowns]);
 // console.log(sol.toString());
 
-nerdamer.setVar("x","-sqrt(-1+z)");
-nerdamer.setVar("y","-2*sqrt(-1+z)+5");
-console.log(nerdamer("(-1/2)*abs(-5+y)*sqrt(-1+z)^(-1)-1").simplify().text());
+// const x = nerdamer("-0.5*sqrt(5)+0.5").simplify().text()
+const x = nerdamer("-2*sqrt(5)+2").simplify().text()
+console.log(x);
+
+// nerdamer.setVar("x","-sqrt(-1+z)");
+// nerdamer.setVar("y","-2*sqrt(-1+z)+5");
+// console.log(nerdamer("(-1/2)*abs(-5+y)*sqrt(-1+z)^(-1)-1").simplify().text());
+
 // let text = nerdamer("2-2*(x/3)").text()
 // console.log(text);
 // const text = nerdamer("2-2*(x/3)").simplify().text()