Question

the sum of two number is 20 and their difference is 10.find the product of the two numbers

Answer 1

Let a>b
so,a+b=20...1

a-b=10..(2)

Adding we got (1)and (2)
2a=30
a=15

REPLACE the VALUE in 1

15+b=20
b=20-15
b=5

PRODUCT
-----+++++++++++
15×5=75

So, their PRODUCTS is 75

Answer 2

$hloo \: here \: is \: ur \: ans \: \\ let \: the \: two \: numbers \: be \: x \: and \: y \\ sum = x + y = 20........1 \\ difference = x - y = 10.......2 \\ from \: eq \: \: 1 \: and \: 2 \\ x + y = 20 \\ x - y = 10 \\ = 2x = 30 \\ x = 30 \div 2 \\ x = 15 \\ sub \: x \: in \: eq \: 1 \\ 15 + y = 20 \\ y = 20 - 15 \\ y = 5$
product = 15 ×5 = 75.....
hope this helps you......