Question

If $y=\frac{1}{2}(3x+7)$ is written in the form $ax+by+c=0,$ which of the following are possible values of a, b and c?

• A. $a=+3,b=-2,c=+7$
• B. $a=+3,b=+2,c=+7$
• C. $a=-3,b=+2,c=-7$
• D. $a=-3,b=-2,c=-7$

Answer 1

Answer: (A), (C)

The correct options are
A

$a=+3,b=-2,c=+7$

C

$a=-3,b=+2,c=-7$

The given equation is $y=\frac{1}{2}(3x+7)$.

Simplifying the equation we get
$2y-3x-7=0$

Rewriting the equation in standard form ax + by + c = 0 we get

$-3x+2y-7=0$

$\therefore$ On comparing the above equation with standard form ax + by +c = 0, we get the values of a, b and c is -3, 2 and -7 respectively.

But the equation can also be written as,

$3x-2y+7=0$
(By multiplying both the sides by (-1))

$\therefore$ On comparing the above equation with standard form ax + by +c = 0, we get the value of a, b and c is +3, -2 and +7 respectively.