Use Elimination: To use elimination, we want to eliminate one of the variables by adding or subtracting the equations. Since the coefficients of x are the same in both equations, we can subtract the second equation from the first to eliminate x. Subtract the second equation from the first: (–3x−4y)−(–3x−3y)=(–15)−(–18)
Subtract Equations: Perform the subtraction.−3x+3x−4y+3y=−15+18The x terms cancel out, and we are left with:−4y+3y=3
Combine Terms: Combine like terms.−y=3
Solve for y: Solve for y by dividing both sides by -1").\(\newline\$y = \frac{3}{-1}\)\(\newline\)\(y = -3\)
Substitute \(y\): Now that we have the value of \(y\), we can substitute it back into one of the original equations to solve for \(x\). Let's use the first equation:\(\newline\)\(–3x − 4y = –15\)\(\newline\)Substitute \(y = -3\) into the equation:\(\newline\)\(–3x − 4(-3) = –15\)
Perform Multiplication: Perform the multiplication and simplify. \(-3x + 12 = -15\)
Isolate x Term: Subtract \(12\) from both sides to isolate the term with \(x\).\(\newline\)\(-3x = -15 - 12\)\(\newline\)\(-3x = -27\)
Solve for x: Divide both sides by \(-3\) to solve for x.\(\newline\)\(x = \frac{-27}{-3}\)\(\newline\)\(x = 9\)
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