Question

Find the value of x in the following equation: x/2 + 2x/5 = 18 A. x = 11/2 B. x = 2 C. x = 255/7 D. x = 20

Answer 1

`(x)/(2) + (2x)/(5) = 18` has the unique solution x = 20.

Explanation:

The equation has the equivalences

`\displaystyle(x)/(2) + (2x)/(5) = 18 \Leftrightarrow x\left( (1)/(2) + (2)/(5) \right) = 18 \Leftrightarrow x \left( (9)/(10) \right) = 18 \Leftrightarrow x = 18 \cdot (10)/(9) = 20.`

Answer 2

Answer: x = 20

Explanation:

Multiply by 10 ( next LCF )

10 ( x / 2 + 2x / 5 ) = 18 * 10

5x + 4x = 180

9x = 180

x = 20