Questions: Используя метод подстановки, решите систему линейных уравнений:
3x - 8y = 99
4y = -32x - 16.
Выразите y из второго уравнения:
3x - 8y = 99
y =
и найдите решение системы линейных уравнений.
x= , y= .
Transcript text: Используя метод подстановки, решите систему линейных уравнений:
\[
\left\{\begin{aligned}
3 x-8 y & =99 \\
4 y & =-32 x-16 .
\end{aligned}\right.
\]
Выразите $y$ из второго уравнения:
\[
\left\{\begin{array}{l}
3 x-8 y=99 \\
y=
\end{array}\right.
\]
и найдите решение системы линейных уравнений.
\[
x=\square, y=\square .
\]
Solution
Solution Steps
Step 1: Write the System of Equations
We start with the given system of linear equations:
\[
\left\{
\begin{aligned}
3x - 8y & = 99 \\
4y & = -32x - 16
\end{aligned}
\right.
\]
Step 2: Rearrange the Second Equation
We rearrange the second equation to express \(y\) in terms of \(x\):
\[
4y = -32x - 16 \implies y = -8x - 4
\]
Step 3: Substitute \(y\) in the First Equation
Next, we substitute \(y = -8x - 4\) into the first equation:
\[
3x - 8(-8x - 4) = 99
\]
Step 4: Simplify the Equation
We simplify the equation:
\[
3x + 64x + 32 = 99 \implies 67x + 32 = 99
\]
Step 5: Solve for \(x\)
Now, we isolate \(x\):
\[
67x = 99 - 32 \implies 67x = 67 \implies x = 1
\]
Step 6: Substitute \(x\) Back to Find \(y\)
We substitute \(x = 1\) back into the equation for \(y\):
\[
y = -8(1) - 4 = -8 - 4 = -12
\]
Step 7: State the Solution
The solution to the system of equations is:
\[
x = 1, \quad y = -12
\]