Question

Y = x - 4 -2x + y = 18 Use elimination pls

Answer 1

Answer:

x = -22 , y = -26

Step-by-step explanation:

Solve the following system:

{y = x - 4 | (equation 1)

y - 2 x = 18 | (equation 2)

Express the system in standard form:

{-x + y = -4 | (equation 1)

-(2 x) + y = 18 | (equation 2)

Swap equation 1 with equation 2:

{-(2 x) + y = 18 | (equation 1)

-x + y = -4 | (equation 2)

Subtract 1/2 × (equation 1) from equation 2:

{-(2 x) + y = 18 | (equation 1)

0 x+y/2 = -13 | (equation 2)

Multiply equation 2 by 2:

{-(2 x) + y = 18 | (equation 1)

0 x+y = -26 | (equation 2)

Subtract equation 2 from equation 1:

{-(2 x)+0 y = 44 | (equation 1)

0 x+y = -26 | (equation 2)

Divide equation 1 by -2:

{x+0 y = -22 | (equation 1)

0 x+y = -26 | (equation 2)

Collect results:

Answer: {x = -22 , y = -26

Answer 2

Answer:

x = -22, y = -26

Step-by-step explanation:

$\left\{\begin{array}{ccc}y=x-4&\text{subtract}\ x\ \text{from both sides}\\-2x+y=18\end{array}\right\\\\\left\{\begin{array}{ccc}-x+y=-4\\-2x+y=18&\text{change the signs}\end{array}\right\\\underline{+\left\{\begin{array}{ccc}-x+y=-4\\2x-y=-18\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad x=-22\\\\\text{Put the value of}\ x\ \text{to the first equation:}\\\\y=-22-4\\y=-26$