Question

two times a number plus three times another numbers equals 13. The sum of the two number is 7. What are the numbers?

Answer 1

The numbers are 20 and - 13

Explanation:

Given as ;

The sum of two numbers = 7

Two times a number and three times another number = 13

So ,Let The first number = x

and The second number = y

According to question

x + y = 7 and ...A

2 × x + 3 × y = 1 ....B

Multiply eq A by 2

I.e 2 × ( x + y ) = 2 × 7

Or, 2 × x + 2 × y = 14

Now solve the both equation

( 2 × x + 3 × y ) - ( 2 × x + 2 × y ) = 1 - 14

Or. ( 2 x - 2 x ) + ( 3 y - 2 y ) = - 13

Or, 0 + y = - 13

∴ y = - 13

Put The value of y in eq A

x + y = 7

Or , x = 7 - y

Or, x = 7 - ( - 13 )

so, x = 7 + 13

∴ x =20

Hence The numbers are 20 and - 13 Answer