20 - (4/5)x ≥ 16 ??
-(4/5)x ≥ -4 now multiply both sides by -1 and change direction of arrow
(4/5) x ≤ 4
x ≤ 5
20 - 4/5x greater than or equal to 16. I did this and got the answer x greater than or equal to -5 but the correct answer is said to be x is less than or equal to 5. i am not sure what i did wrong. thanks
2 answers
I will first assume the second term is 4x/5 and not 4/(5x)
If 20 - 4x/5 >or= 16
-4x/5 >or= -4
-4x >or= 20
Now here is where you probably went wrong: When you multiply or divide both sides of an inequality by a negative number, you must change the direction of the > or < sign.
Divide by -4 and you get
x <or= 5
If 20 - 4x/5 >or= 16
-4x/5 >or= -4
-4x >or= 20
Now here is where you probably went wrong: When you multiply or divide both sides of an inequality by a negative number, you must change the direction of the > or < sign.
Divide by -4 and you get
x <or= 5