39.0k views
5 votes
For which values of (A) the system has at least one solution

For which values of (A) the system has at least one solution-example-1

1 Answer

4 votes

Answer

The values of a that ensures that the system has at least one solution is

a > (21/127)

Step-by-step explanation

We are told to find the values of a that ensures that the system has at least one solution. The system of equations include

3 (a - 5x) < 1 + x

2 - (x/2) > 3 + 5 (x - a)

To do this, we need to solve the expressions

3 (a - 5x) < 1 + x

3a - 15x < 1 + x

We can rewrite this as

1 + x > 3a - 15x

x + 15x > 3a - 1

16x > 3a - 1

Divide both sides 16


\begin{gathered} (16x)/(16)>(3a-1)/(16) \\ x>(3a)/(16)-(1)/(16) \end{gathered}

We then solve the second one. But to do this, let's multiply through by 2

2 - (x/2) > 3 + 5 (x - a)

4 - x > 6 + 10 (x - a)

we can rewrite as

6 + 10 (x - a) < 4 - x

6 + 10x - 10a < 4 - x

10x + x < 10a - 6 + 4

11x < 10a - 2

Divide both sides by 11


\begin{gathered} (11x)/(11)<(10a-2)/(11) \\ x<(10a)/(11)-(2)/(11) \end{gathered}

The two solutions are

x > (3a/16) - (1/16)

x < (10a/11) - (2/11)

To find a lasting solution, we need the inequality sign to be the same, so, we need to multiply through one of the equations by -1

x > (3a/16) - (1/16)

-x < (-3a/16) + (1/16)

So, the system of equations become

-x < (-3a/16) + (1/16)

x < (10a/11) - (2/11)

We can then add the two equations

-x + x < (-3a/16) + (1/16) + (10a/11) - (2/11)

0 < (-3a/16) + (10a/11) + (1/16) - (2/11)

0 < -0.1875a + 0.9091a + 0.0625 - 0.1818

0 < 0.7216a - 0.1193

Rewrite

0.7216a - 0.1193 > 0

0.7216a > 0.1193

Divide both sides by 0.7216

(0.7216a/0.7216) > (0.1193/0.7216)

a > 0.1653

a > (21/127)

Hope this Helps!!!

User Peter DeGregorio
by
7.7k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories