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Question
Draw the graph of the following equations and find their point of intersection.
x – 2y = 0 and 2x + 3y = 7
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Solution

1. Solve for y in both equations
To graph the lines, it is easiest to express them in slope-intercept form (y = mx + c):
Equation 1: x – 2y = 0
⇒ 2y = x
⇒ `y = 1/2 x`
Equation 2: 2x + 3y = 7
⇒ 3y = 7 – 2x
⇒ `y = (7 - 2x)/3`
2. Determine points for plotting
We can find two points for each line to draw them accurately:
For x – 2y = 0:
If x = 0, y = 0.
Point: (0, 0)
If x = 4, y = 2.
Point (4, 2).
For 2x + 3y = 7:
If x = 2, `y = (7 - 2(2))/3` = 1.
Point: (2, 1).
If x = 3.5, `y = (7 - 2(3.5))/3` = 0.
Point: (3.5, 0).
3. Calculate the intersection point
To find the intersection algebraically, substitute x = 2y (From equation 1) into equation 2:
2(2y) + 3y = 7
4y + 3y = 7
7y = 7
⇒ y = 1
Substituting y = 1 back into x = 2y:
x = 2(1)
x = 2
The two lines intersect at the point (2, 1).
