Question

if 7 is added to the square of and integer, the result is 2 less than 10 times that integer. find the integer

Answer 1

The integer is 1 or 9.

Explanation:

Let the integer be x, then:

x^2 + 7 = 10x - 2

x^2 - 10x + 9 = 0

(x - 9)(x - 1) = 0

x = 1, 9.

Verifying

9^2 + 7 = 88

10*9 - 2 = 88 So 9 is correct.

1^2 + 7 = 8

10*1 - 2 = 8 So 1 is also correct.