bases on the system of equations, what is the value of the product xy? 4x-y=3y+7 x+8y=4
Solve the following system:
{4 x-y = 3 y+7 | (equation 1)
x+8 y = 4 | (equation 2)
Express the system in standard form:
{4 x-4 y = 7 | (equation 1)
x+8 y = 4 | (equation 2)
Subtract 1/4 × (equation 1) from equation 2:
{4 x-4 y = 7 | (equation 1)
0 x+9 y = 9/4 | (equation 2)
Multiply equation 2 by 4/9:
{4 x-4 y = 7 | (equation 1)
0 x+4 y = 1 | (equation 2)
Divide equation 2 by 4:
{4 x-4 y = 7 | (equation 1)
0 x+y = 1/4 | (equation 2)
Add 4 × (equation 2) to equation 1:
{4 x+0 y = 8 | (equation 1)
0 x+y = 1/4 | (equation 2)
Divide equation 1 by 4:
{x+0 y = 2 | (equation 1)
0 x+y = 1/4 | (equation 2)
Collect results:
Answer: |x = 2 and y = 1/4
