Y10 Summer Holidays Homework Units 9/10/11: Week 5

Overview
1
2
3
4
5
6
7

Question Progress
Homework Progress: [tex]$7 / 46$[/tex]

Solve the simultaneous equations:

[tex]\[
\begin{array}{l}
2x + 6y = 0 \\
3x - 5y = -7
\end{array}
\][/tex]

Optional working:



Answer :

Certainly! Let's solve the given system of simultaneous equations step-by-step:

Given equations:
[tex]\[ \begin{cases} 2x + 6y = 0 \quad \text{(1)}\\ 3x - 5y = -7 \quad \text{(2)} \end{cases} \][/tex]

Step 1: Solve Equation (1) for [tex]\( x \)[/tex] in terms of [tex]\( y \)[/tex].

[tex]\[ 2x + 6y = 0 \][/tex]

Subtract [tex]\( 6y \)[/tex] from both sides:

[tex]\[ 2x = -6y \][/tex]

Divide both sides by 2:

[tex]\[ x = -3y \quad \text{(3)} \][/tex]

Step 2: Substitute Equation (3) into Equation (2).

Replace [tex]\( x \)[/tex] in Equation (2):

[tex]\[ 3(-3y) - 5y = -7 \][/tex]

Simplify:

[tex]\[ -9y - 5y = -7 \][/tex]

Combine like terms:

[tex]\[ -14y = -7 \][/tex]

Step 3: Solve for [tex]\( y \)[/tex].

Divide both sides by [tex]\(-14\)[/tex]:

[tex]\[ y = \frac{-7}{-14} \][/tex]

Simplify:

[tex]\[ y = \frac{1}{2} \][/tex]

Step 4: Substitute [tex]\( y = \frac{1}{2} \)[/tex] back into Equation (3) to solve for [tex]\( x \)[/tex].

[tex]\[ x = -3 \left(\frac{1}{2}\right) \][/tex]

Simplify:

[tex]\[ x = -\frac{3}{2} \][/tex]

Therefore, the solution to the system of equations is:

[tex]\[ x = -\frac{3}{2} \][/tex]
[tex]\[ y = \frac{1}{2} \][/tex]

So the answer is:

[tex]\[ \left( x, y \right) = \left( -\frac{3}{2}, \frac{1}{2} \right) \][/tex]

That's the detailed step-by-step solution for solving these simultaneous equations.