Suppose that Eldi has x years old now :
x + 4 = 3 × ( x - 10 )
x + 4 = 3x - 30
Add both sides 30
x + 4 + 30 = 3x - 30 + 30
x + 34 = 3x
Subtract both sides x
x - x + 34 = 3x - x
34 = 2x
2x = 34
Divide both sides by 2
2x ÷ 2 =34 ÷ 2
x = 17
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Thus Eldi is 17 .
