use a consistent (and recommended) invocation

./x is recommended over running ./x.py directly,
and is the more commonly-used invocation of bootstrap in the guide
diff --git a/src/autodiff/installation.md b/src/autodiff/installation.md
index c9b28dc..92e79b2 100644
--- a/src/autodiff/installation.md
+++ b/src/autodiff/installation.md
@@ -13,7 +13,7 @@
 
 Afterwards you can build rustc using:
 ```bash
-./x.py build --stage 1 library
+./x build --stage 1 library
 ```
 
 Afterwards rustc toolchain link will allow you to use it through cargo:
@@ -25,10 +25,10 @@
 You can then run our test cases:
 
 ```bash
-./x.py test --stage 1 tests/codegen/autodiff
-./x.py test --stage 1 tests/pretty/autodiff
-./x.py test --stage 1 tests/ui/autodiff
-./x.py test --stage 1 tests/ui/feature-gates/feature-gate-autodiff.rs
+./x test --stage 1 tests/codegen/autodiff
+./x test --stage 1 tests/pretty/autodiff
+./x test --stage 1 tests/ui/autodiff
+./x test --stage 1 tests/ui/feature-gates/feature-gate-autodiff.rs
 ```
 
 Autodiff is still experimental, so if you want to use it in your own projects, you will need to add `lto="fat"` to your Cargo.toml 
diff --git a/src/offload/installation.md b/src/offload/installation.md
index 2536af0..8cfec44 100644
--- a/src/offload/installation.md
+++ b/src/offload/installation.md
@@ -13,7 +13,7 @@
 
 Afterwards you can build rustc using:
 ```bash
-./x.py build --stage 1 library
+./x build --stage 1 library
 ```
 
 Afterwards rustc toolchain link will allow you to use it through cargo:
@@ -40,7 +40,7 @@
 ## Testing
 run
 ```
-./x.py test --stage 1 tests/codegen/gpu_offload
+./x test --stage 1 tests/codegen/gpu_offload
 ```
 
 ## Usage