Question

5x=4y+8 3y=3x-3 using elimination

Answer 1

Let's rewrite the equation with x and y on the left side of the equal sign.  
5x-4y=8 --------(1) 
3x-3y=3---------(2)  
Divide equation (2) by 3, 
x - y= 1 
now we have, 
5x-4y = 8 --------(1) 
x - y = 1 ---------(2)  
To eliminate x, multiply equation (2) by 5. This makes both the coefficients of x to be 5. Subtract the second equation from the first equation.  
5x - 4y = 8 
(2) * 5 5x - 5y = 5 
(-) (+) (-) 
---------------- 
 0x +y =3
 Therefore, y=3 
 Substitute the value of y, in any one of the two equations. Let's substitute y in the second equation.
 x-3=1
 x=4 
 x=4 and y=3