-5(x+7)<-10
ok so we need to distribute the -5 into the x and 7.
-5x+-35<-10
then, we combine like terms.
-5x+-35<-10
+35 +35
-5x<25
Then, we get the variable to be by itself.
-5x<25
divide by -5
x<-5
Hope this helps! If you still don't get it, ask me.