Restropective Ages

Relevant wiki: Setting Up Equations

Let Beth's currently unknown age be $x$ . In two years time, Beth's age will be the following expression: $x+2$ Beth has also told us that she'll be twice the age she was five years prior to her current age. This means that her age will be this next expression: $2(x-5)$ Since both expressions represent the same age, we can equate them and solve for x: $\begin{aligned} x+2 &=2(x-5)\\ x+2 &=2x-10\\ -x &=-12\\ x &=12 \end{aligned}$ From this, we can conclude that Beth is $12$ years old.

suppose, his present age is "x" years.

so,

2*(x-5) = x +2

or, 2x -10 = x + 2

or, 2x - x = 2 + 10

or, x = 12

Suppose the current age of Beth is $B$ years

$\Rightarrow 2(B - 5) = B + 2$

$\Rightarrow 2B - 10 = B + 2$

$\Rightarrow 2B - B = 2 + 10$

Therefore $B = \boxed{12}$ years old

let his present age is "x" years then

• 2*(x-5) = x +2
• 2x -10 = x + 2
• 2x - x = 2 + 10
• x = 12