### Brain Teasers

# (a x a) x 2 = (a + 5) x 81

Math
Math brain teasers require computations to solve.

I have an integer which, when squared and then multiplied by two is equal to that integer five higher than it multiplied by eighty one.

(a x a) x 2 = (a + 5) x 81

What is my number?

(a x a) x 2 = (a + 5) x 81

What is my number?

### Hint

Square a number and then multiply it by two. Divide your answer by the number five higher than it and if the answer is less than 81 it is too low. If the answer is more than 81 it is too high.### Answer

My number is 45.(a = 45)

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