Solve the following system:
{5 x - 4 y = -4 | (equation 1)
2 x - 4 y = -16 | (equation 2)
Subtract 2/5 × (equation 1) from equation 2:
{5 x - 4 y = -4 | (equation 1)
0 x - (12 y)/5 = (-72)/5 | (equation 2)
Multiply equation 2 by -5/12:
{5 x - 4 y = -4 | (equation 1)
0 x+y = 6 | (equation 2)
Add 4 × (equation 2) to equation 1:
{5 x+0 y = 20 | (equation 1)
0 x+y = 6 | (equation 2)
Divide equation 1 by 5:
{x+0 y = 4 | (equation 1)
0 x+y = 6 | (equation 2)
x = 4 and y = 6
Multiply first equation by - 1 to get
-5x+4y=4 add this to the second equation to get
-3x=-12 so x = 4
Substitute this value of 'x' in to one of the equations to get 'y'
5(4)-4y = -4
20-4y =-4
-4y = -24 y = 6