Question

Find the product of all constants t such that the quadratic x^2 tx - 9 can be factored in the form (x a)(x b), where a and b are integers.

Answer 1

729

Explanation:

Answer 2

product of the constants P will be

P = 12

Explanation:

the quadratic equation

F= x² + t*x - 9

has as solution

a and b= [-t ± √( t² - 4*1*(-9)) ] /2]

then

a - b = -t/2

a= b - t/2

since b is an integer , then t/2 should be an integer , then t=2*n , where n is any integer

also

a and b= [-t ± √( t² - 4*1*(-9)) ] /2] = [-2*n ± √(4*n²+36 )] /2 = -n ± n √ (1+9/ n²]

since n are integers , then √ (1+9/ n²] should be and integer and therefore

9/ n² should be an integer. Then the possible values of n are

n=1 and n=3

therefore the possible values of t are

t₁=2*1 = 2

t₂=2*3 = 6

the product of the constants P will be

P=t₁*t₂ = 12