Question

What value of x is in the solution set of –5x – 15 > 10 + 20x? –2 –1 0 1

Answer 1

x< -5/3

x is less than -5/3 , so answer = -2

Explanation:

`5x - 15 > 10 + 20x\\\mathrm{Add\:}15\mathrm{\:to\:both\:sides}\\\\5x-15+15>10+20x+15\\\mathrm{Simplify}\\\\5x>20x+25\\\\\mathrm{Subtract\:}20x\mathrm{\:from\:both\:sides}\\\\5x-20x>20x+25-20x\\\\\mathrm{Simplify}\\\\-15x>25\\\\\mathrm{Multiply\:both\:sides\:by\:-1\:\left(reverse\:the\:inequality\right)}\\\\\left(-15x\right)\left(-1\right)<25\left(-1\right)\\\\\mathrm{Simplify}\\\\15x<-25\\\\\mathrm{Divide\:both\:sides\:by\:}15\\\\(15x)/(15)<(-25)/(15)\\\\x<-(5)/(3)`

Answer 2

-2

Explanation:

5x – 15 > 10 + 20x

Subtract 5x from each side

5x – 15-5x > 10 + 20x-5x

-15 > 10+15x

Subtract 10 from each side

-15-10 >15x

-25 > 15x

Divide each side by 15

-25/15 > x

-5/3 > x

X must be less than -1 2/3

The only value that is less than -1 2/3 is -2