158k views
3 votes
7 times a number is 8 less than the square of that number. Find the negative solution ​

User Nedelka
by
4.9k points

1 Answer

5 votes

Answer:
x = -1

Explanation:

Let the number be x .

7 times the number implies
7x

7 times a number is 8 less than the square of that number , interpreting this , we have


7x +8 = x^(2)

re - arranging , we have :


x^(2) - 7x - 8 = 0

factorizing the quadratic expression , we have:


(x-8)(x+1) = 0

either
(x-8) =0 or
(x+1) = 0

Therefore :


x = 8 or
x = -1

Therefore , the negative solution is -1

User Victor Perov
by
5.0k points