Question

Find two positive numbers which have a difference of 5 and whose product is 84.​

Answer 1

Answer:

let the one number be x

onother be y

according to question

x-y=5

x=5+y

onsubstituting this value in xy= 84

we get (5+y)y=84

y^2+5y=84

y^2+5y-84=0

by using factorisation method we get

y^2+12y-7y-84=0

y(y-7)-7(y+12)

so (y-7)(y+12) are the two factors so the two answers of the equation are y=7 and y=-12

so the one positive number is 7

other is 7.x=84

so x is 12

therefore the two numbers are 12 and5

Answer 2

$x \times (x - 5)$

$= 84$

$x - 5 = 84 \div x$

${x}^{2} = 79$