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Solve the following system of equations by graphing:

x - 3y = 9
y - 1 = 0

User Jdwyah
by
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2 Answers

2 votes

Final answer:

To solve the provided system of equations, each equation is converted into slope-intercept form and graphed. The solution is where the line y=(1/3)x-3 intersects the horizontal line y=1.

Step-by-step explanation:

The student is tasked with solving a system of equations consisting of x - 3y = 9 and y - 1 = 0 by graphing. To graph these equations, we must first rearrange each into slope-intercept form (y = mx + b), where m represents the slope and b represents the y-intercept. For the first equation, this gives us y = ⅓x - 3 and the second equation is already in slope-intercept form, y = 1. By creating a table of values or using the slope and intercept, we plot these two lines on a graph. The solution to the system will be the point where both lines intersect.

To graph the first equation, we start at the y-intercept (0, -3) and use the slope of ⅓ to rise 1 unit and run 3 units horizontally. We then plot the second equation as a horizontal line at y = 1. The intersection of these two lines represents the solution to the system of equations, which can be identified by observing the point on the graph where both lines meet.

User Lolo Me
by
8.4k points
4 votes

Final answer:

The solution to the system of equations by graphing is found by plotting both equations on a coordinate plane. The first equation is converted to slope-intercept form and graphed, while the second equation is a horizontal line. Their point of intersection is the solution, which is (12, 1).

Step-by-step explanation:

To solve the system of equations by graphing, let's first rewrite the equation 'x - 3y = 9' in slope-intercept form, which is 'y = mx + b' where 'm' is the slope and 'b' is the y-intercept. We solve for 'y' and get 'y = rac{1}{3}x - 3'. Now, the second equation 'y - 1 = 0' simplifies to 'y = 1'. This is a horizontal line that crosses the y-axis at 1.

To graph 'y = rac{1}{3}x - 3', pick several values of 'x', substitute them into the equation, and solve for 'y' to find corresponding points. Plot these points on a coordinate plane and draw a line through them.

The slope is ¼, which means 'rise over run' is 1 for every 3 units of 'x'. To graph 'y = 1', draw a straight line parallel to the x-axis that crosses the y-axis at 1.

The solution to the system is the point where the two lines intersect. Since 'y = 1' is a horizontal line, it intersects 'y = rac{1}{3}x - 3' at the point where x satisfies ¼x - 3 = 1. Solving for 'x' gives 'x = 12'. Therefore, the solution to the system of equations is (12, 1).

User Sbrichards
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7.4k points