Question

Solve, graphically, the following pairs of equation :
3x + 7y = 27
8 - y = `(5)/(2)x`

Answer 1

3x + 7y = 27
⇒ 3x = 27 - 7y
⇒ x = `(27 - 7y)/(3)`

The table for 3x + 7y = 27 is

X	9	2	-5
Y	0	3	6

Also, we have
8 - y = `(5)/(2)x`
⇒ x = (8 - y) x `(2)/(5)`
The table for 5x + 2y = 16 is

X	2	4	0
Y	3	- 2	8

Plotting the points we get the following required graph:

From the above graph, it is clear that the two lines 3x + 7y = 27 and 8 - y = `(5)/(2)x` intersect at the point (2,3)