Question

1. If the system of equations 4x + py = 21 and px - 2y = 15 has unique solutions,
then which of the following is not the possible value of p?
(2) 2 (b) – 2 (c) 24
(d)
-8​

Answer 1

Answer:

d) -8

Step-by-step explanation:

the value of p will be -8

Answer 2

For all real values of p the equations have unique solution.

Step-by-step explanation:

The two equations are

4x + py = 21 ........... (1) and

px - 2y = 15 ............. (2)

where p is an unknown constant.

The slope of equation (1) is $- \frac{4}{p}$ and the slope of the equation (2) is $\frac{p}{2}$

So, to get a unique solution for equations (1) and (2) we have the condition

$- \frac{4}{p} \neq \frac{p}{2}$

Now, for all real value of p, this relation is valid.

Therefore, for all real values of p, the equations have a unique solution. (Answer)