26.5k views
4 votes
The difference of the square of a number and 28 is equal to 3 times that number

User Obey
by
8.2k points

1 Answer

2 votes

Answer:

- 4, 7

Explanation:

Let the required number be x.

Therefore, according to the given condition:


{x}^(2) - 28 = 3x \\ {x}^(2) - 3x - 28 = 0 \\ {x}^(2) - 7x + 4x - 28 = 0 \\ x(x - 7) + 4(x - 7) = 0 \\ (x - 7)(x + 4) = 0 \\ x - 7 = 0 \: or \: x + 4 = 0 \\ x = 7 \: or \: x = - 4 \\

User Fbrandel
by
7.4k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories