Advertisements
Advertisements
Question
Draw a graph of the equation 3x - y = 7. From the graph find the value of:
(i) y, when x = 1
(ii) x, when y = 8
Advertisements
Solution
We have
3x - y = 7
⇒ -y = 7 - 3x
⇒ y = 3x - 7
When x = -2
⇒ y = -6 - 7
= -13
When x = 0
⇒ y = -7
When x = 2
⇒ y = 6 - 7
= -1
| x | -2 | -1 | 0 | 1 | 2 |
| y | -13 | -10 | -7 | -7 | -1 |

Thus ordered pairs of 3x - y = 7 are {(-2, -13), (-1, -10), (0, -7), (1, -4), (2, -1)}. Hence graph is as below.
(i) y, when x = 1
From graph we find that y = -4, when x = 1
(ii) x, when y = 8
From graph we find that x = 5, when y = 8.
APPEARS IN
RELATED QUESTIONS
Draw the graphs of the following equations on the same system of co-ordinates. Write the co-ordinates of their points of intersection.
x + 4 = 0, y - 1 = 0, 2x + 3 = 0, 3y - 15 = 0
Draw the graph of the equation given below.
x + y = 2
Draw the graph of the equation given below.
3x - y = 0
Draw the graph for the linear equation given below:
y + 6 = 0
Draw the graph for the linear equation given below:
y = - 2x
Draw the graph for the linear equation given below:
y = x
Draw the graph for the linear equation given below:
y = - x + 4
Draw the graph for the linear equation given below:
x - 3 = `(2)/(5)(y + 1)`
For the pair of linear equations given below, draw graphs and then state, whether the lines drawn are parallel or perpendicular to each other.
y = x - 3
y = - x + 5
The graph of 3x + 2y = 6 meets the x=axis at point P and the y-axis at point Q. Use the graphical method to find the co-ordinates of points P and Q.
