Question

Aastha multiplied two numbers and got (–4) as the product. She then subtracted the second number from the first and got the answer as 5. The two numbers are _______. Choose the correct answer: (a) 2, –3 (b) 1, –4 (c) –1, 4 (d) 5, –1

Answer 1

Answer: let the 2 numbers be 'a' and 'r'

a * r = -4........(1)

r - a = 5....(2)

from (2)

r = a+5.....(3)

put the value of (3) in (1)

a * (a+5) = -4

a^2 + 5a + 4 = 0

on solving this quadratic eq. we have

a^2 + a + 4a + 4 = 0

a(a+1) + 4(a+1) = 0

(a+4) * (a+1) = 0

a can't be equal to -1 because then r= 4 which won't satisfy the 2nd condition.

hence a= -4 and then r= 1

therefore correct answer is (B)