How do you solve -4(x+6)-9>2(x-9)4(x+6)9>2(x9)?

1 Answer
Jul 3, 2017

See a solution process below:

Explanation:

First, expand the terms in parenthesis on each side of the inequality by multiplying each term within the parenthesis by the term outside the parenthesis:

color(red)(-4)(x + 6) - 9 > color(blue)(2)(x - 9)4(x+6)9>2(x9)

(color(red)(-4) * x) + (color(red)(-4) * 6) - 9 > (color(blue)(2) * x) - (color(blue)(2) * 9)(4x)+(46)9>(2x)(29)

-4x - 24 - 9 > 2x - 184x249>2x18

-4x - 33 > 2x - 184x33>2x18

Now, add color(red)(4x)4x and color(blue)(18)18 to each side of the inequality to isolate the xx term while keeping the inequality balanced:

color(red)(4x) - 4x - 33 + color(blue)(18) > color(red)(4x) + 2x - 18 + color(blue)(18)4x4x33+18>4x+2x18+18

0 - 15 > (color(red)(4) + 2)x - 0015>(4+2)x0

-15 > 6x15>6x

Now, divide each side of the inequality by color(red)(6)6 to solve for xx while keeping the inequality balanced:

-15/color(red)(6) > (6x)/color(red)(6)156>6x6

-(3 xx 5)/color(red)(3 xx 2) > (color(red)(cancel(color(black)(6)))x)/cancel(color(red)(6))

-(color(red)(cancel(color(black)(3))) xx 5)/color(red)(color(black)(cancel(color(red)(3))) xx 2) > x

-5/2 > x

To state the solution in terms of x we can reverse or "flip" the entire inequality:

x < -5/2