Question

1. \

$$\begin{cases} 5x + 2y = -3 \\\\ 3x + 3y = 9 \\end{cases}$$

Explanation:

Step1: Simplify the second equation

Divide the second equation \(3x + 3y = 9\) by 3, we get \(x + y = 3\), then express \(y\) as \(y = 3 - x\).

Step2: Substitute \(y\) into the first equation

Substitute \(y = 3 - x\) into \(5x + 2y = -3\), we have \(5x + 2(3 - x) = -3\).
Expand and simplify: \(5x + 6 - 2x = -3\), \(3x + 6 = -3\), \(3x = -9\), so \(x = -3\).

Step3: Find the value of \(y\)

Substitute \(x = -3\) into \(y = 3 - x\), we get \(y = 3 - (-3) = 6\).

Answer:

The solution of the system of equations is \(x = -3\), \(y = 6\)