Get detailed and accurate responses to your questions on IDNLearn.com. Our platform provides detailed and accurate responses from experts, helping you navigate any topic with confidence.

Solve the system of equations:

[tex]\[
\begin{cases}
-2x - \frac{2y}{4} = 12 \\
\frac{x}{5} - \frac{y}{3} = 5
\end{cases}
\][/tex]


Sagot :

To solve the system of equations:

1. [tex]\(-2x - \frac{2y}{4} = 12\)[/tex]
2. [tex]\(\frac{x}{5} - \frac{y}{3} = 5\)[/tex]

We'll start by simplifying the equations.

### Simplifying the First Equation:
The first equation is:
[tex]\[ -2x - \frac{2y}{4} = 12 \][/tex]
Simplify [tex]\(\frac{2y}{4}\)[/tex] to [tex]\(\frac{y}{2}\)[/tex]:
[tex]\[ -2x - \frac{y}{2} = 12 \][/tex]
To eliminate the fraction, multiply the entire equation by 2:
[tex]\[ -4x - y = 24 \quad \Rightarrow \quad 4x + y = -24 \quad \text{(Equation 3)} \][/tex]

### Simplifying the Second Equation:
The second equation is:
[tex]\[ \frac{x}{5} - \frac{y}{3} = 5 \][/tex]
To eliminate the fractions, multiply the entire equation by 15 (which is the least common multiple of 5 and 3):
[tex]\[ 15 \left(\frac{x}{5}\right) - 15 \left(\frac{y}{3}\right) = 15 \times 5 \\ 3x - 5y = 75 \quad \text{(Equation 4)} \][/tex]

Now, we have the simplified system of equations:
1. [tex]\(4x + y = -24\)[/tex]
2. [tex]\(3x - 5y = 75\)[/tex]

### Solving the System of Equations:
We can use the method of substitution or elimination. Here, we'll use elimination.

Step 1: Align the equations:
[tex]\[ 4x + y = -24 \quad \text{(Equation 3)} \][/tex]
[tex]\[ 3x - 5y = 75 \quad \text{(Equation 4)} \][/tex]

Step 2: Make the coefficients of y in both equations equal by multiplying the first equation by 5:
[tex]\[ 5(4x + y) = 5(-24) \\ 20x + 5y = -120 \quad \text{(Equation 5)} \][/tex]

Step 3: Add Equation 5 and Equation 4 to eliminate y:
[tex]\[ (20x + 5y) + (3x - 5y) = -120 + 75 \\ 20x + 3x + 5y - 5y = -120 + 75 \\ 23x = -45 \\ x = \frac{-45}{23} \\ x = -\frac{45}{23} \][/tex]

Step 4: Substitute [tex]\(x\)[/tex] back into Equation 3 to find [tex]\(y\)[/tex]:
[tex]\[ 4 \left( -\frac{45}{23} \right) + y = -24 \\ -\frac{180}{23} + y = -24 \][/tex]

First, rewrite [tex]\(-24\)[/tex] as a fraction:
[tex]\[ -24 = -\frac{552}{23} \][/tex]

So:
[tex]\[ -\frac{180}{23} + y = -\frac{552}{23} \\ y = -\frac{552}{23} + \frac{180}{23} \\ y = -\frac{552 - 180}{23} \\ y = -\frac{372}{23} \][/tex]

Thus:
[tex]\[ y = -\frac{372}{23} \][/tex]

Therefore, the solution to the system of equations is:
[tex]\[ x = -\frac{45}{23}, \quad y = -\frac{372}{23} \][/tex]