Question

Solve the 8x+3y=9 3x+2y =4 by elimination metho

Answer 1

Heya!!!

8x + 3y = 9 -------- (1) 
3x + 2y = 4 -------- (2)

In elimination method, we have to make any one variable same,

So, let's cancel 'x' variable by multiplying 8 in (2) and 3 in (1)

So,

{8x + 3y = 9} 3
{3x + 2y = 4} 8

⇒ 24x + 9y  = 27 ---------- (3)
    24x + 16y = 32 --------- (4)

By subtracting (4) from (3), we get, 

  24x + 9y  =   27
- 24x - 16y = - 32

 - 7y = - 5
     y = - 5 / -7 
     y = 5 / 7  
 
and from (1)

8x + 3 (5 / 7) = 9 
8x + 15 / 7 = 9 
56x + 15 = 63
56x = 63 - 15
56x = 48 
x     = 48 / 56
x     = 6 / 7 


So, 

x = 6 / 7 and y = 5 / 7 


Ways to cross - check the answer (EXTRA)

from (1)
8 (6 / 7) + 3 (5 / 7) 
48 / 7 + 15 / 7
48 + 15 / 7 
63 / 7
= 9 , which is same as given in (1),

So the solution is verified.



Thanks