solve the inequality. -x less than or equal to 5 explain.
hint -1(-1)=1
i just dont know how to solve it with the less than or equal sign
if you multiply both sides by a negative (or divide both sides by a negative) make sure you flip the direction of the inequality sign
just like if you have 3>2 and you multiply both sides by -1 you -3<-2
okay so i multiply both sides by one then?
so what happens when you multiply both sides by -1?
the hint was (-1)(-1)=1 we want just x by itself 1(-1)=-1 nothing changes there so definitely multiplying both sides by -1
5<-1?
no you have -x<=5
multiply both sides of that by -1
oh so do i do anything else now?
@freckles
@Directrix
have you multiplied both sides by -1 yet if so can i see the result
yeah you would get x<=-5 or 5
what is -1 times 5?
-5
so there is no or there
what happens to the direction of the inequality
it switches sides?
Recall if you have 3>2 and you decide you are going to multiply by -1 on both sides you have -3<-2
yes flip the inequality sign
okay so then it would be x>-5
\[-x \le 5 \\ (-1)(-x) \ge (-1)(5) \text{ inequality sign has been flipped since we multiply/divide } \\ \text{ both sides by a negative } x \ge -5 \]
@Sadworld
are you still stuck?
we already have the answer
x is greater than or equal to -5
kinda like its just im not the best at math it takes me a while idk
which part confuses you
the whole thing, its like a tiny puzzle you cant figure which goes with which
you have \[-x \le 5 \\ \text{ to get } x \text{ by itself you need } -1(-x)=x \text{ on the left } \\ \text{ \to get that you need to multiply both sides by -1 } \\ (-1)(-x) \ge (-1)(5) \\ x \ge -5 \\ \text{ nothing else to do }\]
the inequality sign changes the direction if you think back to non-variable numbers this is easy to see
you know -3<-2
if you multiply both sides by -1 you get 3>2
notice the inequality sign doesn't keep the same direction due to the multiplying/dividing by negative numbers on both sides
Join our real-time social learning platform and learn together with your friends!