Question

solve the following pair of linear equation by the elimination method and the substitution method X + Y =5 and2x-3y=4​

Answer 1

Answer:

x + y =5 and 2x –3y = 4

By elimination method

x + y =5

2x –3y = 4

Multiplying equation 

2x + 2y = 10

2x –3y = 4

Subtracting equation

5y = 6

y = 6/5

Putting the value in equation 

x = 5 - (6/5) = 19/5

Hence, x = 19/5 and y = 6/5

Step-by-step explanation:

Answer 2

SUBSTITUTION METHOD :

$x+y=5\\x=y-5----(i)\\2x-3y=4----(ii)$

Put value of (i) in equation (ii) :

$2(5-y)-3y=4\\10-2y-3y=4\\10-5y=4\\-5y=4-10\\y=6/5$

Put value of y in (i) equation :

$x =5-6/5\\x=(25-6)/5\\x=19/5$

ELIMINATION METHOD :

$x + y =5----(i)\\2x-3y =4----(ii)$

Multiply (i) equation by 2 and subtract equation (ii) from (i) :

$2x+2y=10\\2x-3y=4\\-------\\5y=6\\y=6/5$

Put value of y in (i) equation :

$x+6/5=5\\x=5-6/5\\x=(25-6)/5\\x=19/5$