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Solve the equation:

(21 - 4x)/(9) +
(8x + 15)/(3) = 2

User Red Orca
by
6.5k points

1 Answer

10 votes

Answer:


x = -(12)/(5)

Explanation:

To solve the equation, isolate x. Whatever you do to isolate x one on side, you must do to the other.

1) Multiply both sides by 9 to get rid of the fractions.


(21-4x)/(9) +(8x+15)/(3) = 2 \\21-4x + 3(8x + 15) =18 \\

2) Distribute the 3 to 8x and 15. Then, combine like terms.


21-4x + 24x + 45 = 18 \\66 + 20x = 18

3) Move the 66 to the other side, subtracting 18 by 66, then divide each side by 20 to finally isolate x.


20x = -48\\x = -(48)/(20) \\x =- (12)/(5)

Thus,
x = -(12)/(5).

User Liz Barrett
by
8.0k points