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If the square of a positive number is decreased by five times the number the result is 36. Find the

number.

please draw out the formula along with answer. show all work

User Shadoninja
by
4.0k points

1 Answer

5 votes

Answer:

The answer is 4

Explanation:

If we let

x equal the number, then,

x 2 + 5 x = 36

The square is indicated with ^ 2 .If we add it to five times that number, or

5 ⋅ x = 5 x , then we get x 2 + 5 x = 36 .

This is a quadratic! We subtract 36 from both sides to get x

2 + 5 x − 36 = 0 .

Solving it, we get

( x − 4 ) ( x + 9 ) .

Remember, though! The number must be positive.

x > 0 .

Therefore the only possible answer is

x = 4 .

Yay!

User Manav Patadia
by
4.8k points