Make: G++: Command Not Found

I've checked similar posts and anyone solve my problem. I's very simple but I'm new with eclipse. I'm trying to make a simple example and I'm having this problem.

the make file is just this

all: hello.exe

clean:
    rm Hello.o Hello.exe

hello.exe: hello.o
    g++ -g -o hello.exe hello.o

hello.o:
    g++ -c -g main.cpp

And I get this error "make: g++: Command not found"

Thanks for helping.