Welcome to Westonci.ca, the place where your questions are answered by a community of knowledgeable contributors. Experience the ease of finding reliable answers to your questions from a vast community of knowledgeable experts. Experience the ease of finding precise answers to your questions from a knowledgeable community of experts.

Graph this system of equations:

[tex]\[
\begin{array}{l}
1.15x + 0.65y = 8.90 \\
x - 3y = -15
\end{array}
\][/tex]


Sagot :

To graph the given system of equations, follow these steps:

System of Equations:
1. [tex]\( 1.15x + 0.65y = 8.90 \)[/tex]
2. [tex]\( x - 3y = -15 \)[/tex]

First, let's find the slope-intercept form ( [tex]\( y = mx + b \)[/tex] ) for both equations.

### Step-by-Step Solution:

1. Rearrange the first equation [tex]\( 1.15x + 0.65y = 8.90 \)[/tex] to slope-intercept form:

[tex]\[ 1.15x + 0.65y = 8.90 \][/tex]

Isolate [tex]\( y \)[/tex]:

[tex]\[ 0.65y = 8.90 - 1.15x \][/tex]

Divide both sides by [tex]\( 0.65 \)[/tex]:

[tex]\[ y = \frac{8.90 - 1.15x}{0.65} \][/tex]

Simplify:

[tex]\[ y = \frac{8.90}{0.65} - \frac{1.15}{0.65}x \][/tex]

[tex]\[ y = 13.69 - 1.77x \][/tex]

So, the first equation in slope-intercept form is:

[tex]\[ y = -1.77x + 13.69 \][/tex]

2. Rearrange the second equation [tex]\( x - 3y = -15 \)[/tex] to slope-intercept form:

[tex]\[ x - 3y = -15 \][/tex]

Isolate [tex]\( y \)[/tex]:

[tex]\[ -3y = -15 - x \][/tex]

Divide both sides by [tex]\( -3 \)[/tex]:

[tex]\[ y = \frac{-15 - x}{-3} \][/tex]

Simplify:

[tex]\[ y = 5 + \frac{1}{3}x \][/tex]

So, the second equation in slope-intercept form is:

[tex]\[ y = \frac{1}{3}x + 5 \][/tex]

### Plotting the Equations:

Now, we will plot these equations on a graph.

1. First Equation: [tex]\( y = -1.77x + 13.69 \)[/tex]

- y-intercept (b): 13.69 (the point where the line crosses the y-axis, set [tex]\( x = 0 \)[/tex] and find [tex]\( y \)[/tex])
- Slope (m): -1.77 (for each unit increase in [tex]\( x \)[/tex], [tex]\( y \)[/tex] decreases by 1.77 units)

2. Second Equation: [tex]\( y = \frac{1}{3}x + 5 \)[/tex]

- y-intercept (b): 5 (the point where the line crosses the y-axis, set [tex]\( x = 0 \)[/tex] and find [tex]\( y \)[/tex])
- Slope (m): [tex]\(\frac{1}{3}\)[/tex] (for each unit increase in [tex]\( x \)[/tex], [tex]\( y \)[/tex] increases by [tex]\(\frac{1}{3}\)[/tex] units)

Steps to plot:

1. Draw the x-axis and y-axis.
2. Mark the y-intercepts for both equations:
- First equation: [tex]\( y = 13.69 \)[/tex]
- Second equation: [tex]\( y = 5 \)[/tex]
3. Use the slopes to find another point on each line:
- For [tex]\( y = -1.77x + 13.69 \)[/tex], from the intercept (0, 13.69), go down 1.77 units and right 1 unit to find another point.
- For [tex]\( y = \frac{1}{3}x + 5 \)[/tex], from the intercept (0, 5), go up [tex]\(\frac{1}{3}\)[/tex] units and right 1 unit to find another point.
4. Draw straight lines through these points.

Interpreting the Graph:

The intersection point of the two lines represents the solution to the system of equations. This is the point where both equations are satisfied simultaneously.

By graphing [tex]\( y = -1.77x + 13.69 \)[/tex] and [tex]\( y = \(\frac{1}{3}\)[/tex] x + 5 \), you will see the point where they intersect. This is the solution to the system.
We appreciate your time. Please come back anytime for the latest information and answers to your questions. Thanks for using our service. We're always here to provide accurate and up-to-date answers to all your queries. Stay curious and keep coming back to Westonci.ca for answers to all your burning questions.