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3 years ago

Solve for x in this equation. 2(3x - 4) = 9(8 + 5x)

Mathematics

2 answers:

Harrizon [31]3 years ago

5 0

2(3x - 4) = 9(8 + 5x)

Mutiply the first bracket by 2

(2)(3x)(2)(-4)= 6x-8

Mutiply the second bracket by 9

(9)(8)(9)(5x)= 72+45x

6x-8= 72+45x

move -8 to the other side , sign becomes +8

6x-8+8= 72+8+45x

6x= 72+8+45x

6x= 80+45x

move +45x to the other side , sign becomes -45x

6x-45x= 80+45x-45x

6x-45x= 80

-39x= 80

divide both sides by -39

-39x/-39= 80/-39

x= -80/39 or x=-2 2/39

Answer: x= -80/39 or x=-2 2/39

stepladder [879]3 years ago

5 0

Answer:

$x=-80/39$

Step-by-step explanation:

We have the equation:

$2(3x - 4) = 9(8 + 5x)$

first we multiply 2 by (3x - 4) in the left side, and multiply 9 by (8 + 5x) in the right side:

$6x-8=72+45x$

now we move all terms with x to the left, and all independent terms to the right:

$6x-45x=72+8\\-39x=80$

finally we divide by (-39) both sides of the equation:

$\frac{-39x}{-39}=\frac{80}{-39} \\x=-\frac{80}{39}$

making this division we get:

$x=-2.0513$

or you can just leave the answer as $x=-80/39$

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