Question

solve using elimination.
4x + y = -1
x - 2y = 20
(□, □)

Explanation:

Step1: Eliminate y by multiplying first equation

Multiply \(4x + y = -1\) by 2: \(8x + 2y = -2\)

Step2: Add the two equations

Add \(8x + 2y = -2\) and \(x - 2y = 20\): \(9x = 18\)

Step3: Solve for x

Divide both sides by 9: \(x = \frac{18}{9} = 2\)

Step4: Substitute x into first equation

Substitute \(x = 2\) into \(4x + y = -1\): \(4(2) + y = -1\) → \(8 + y = -1\)

Step5: Solve for y

Subtract 8: \(y = -1 - 8 = -9\)

Answer:

\((2, -9)\)