Answer:
see explanation
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + b ( m is the slope and b the y- intercept )
Calculate m using the slope formula
m = 
with (x₁, y₁ ) = (0, 3) and (x₂, y₂ ) = (4, 0) ← 2 points on the line
m =
=
= - 
The y- intercept is where the line crosses the y- axis
The line crosses the y- axis at (0, 3 ) ⇒ b = 3
(b)
y = -
x + 3 ← equation of line
Answer:

Step-by-step explanation:
By putting the numbers in the given equation,

2x + 3 + 3x = 7x + 9
5x + 3 = 7x + 9
(5x + 3) - 7x = (7x + 9) - 7x
(5x - 7x) + 3 = 9
-2x + 3 = 9
(-2x + 3) - 3 = 9 - 3
-2x = 6

-x = 3
x = -3
Therefore, our equation is correct which has a negative result.
In place of 6 if we use 8, value of x will be negative again.