Question

State whether the system is consistent and independent, consistent and dependent or inconsistent.

Answer 1

Answer:

The correct option is 1.

Step-by-step explanation:

Inconsistent system: If the given system has no solutions, then it is an inconsistent system.

Consistent and independent system: If the given system has only one solutions, then it is an consistent and independent system.

Consistent and dependent system: If the given system has many solutions, then it is an consistent and dependent system.

The given equations are

$x+3y=18$        .... (1)

$-x+2y=7$         ..... (2)

Add both equations.

$x+3y-x+2y=18+7$

$5y=25$

$y=5$

Substitute this value in equation (1).

$x+3(5)=18$

$x+15=18$

$x=3$

The system of equations has only one solution, i.e.,(3,5).

Therefore the given system is consistent and independent. Option 1 is correct.

Answer 2

Answer:

Given system is consistent and independent.

Step-by-step explanation:

We have given two equations.

x+3y  = 18             eq(1)

-x+2y = 7              eq(2)

We have to find whether the system is consistent, inconsistent and dependent or independent.

Consistent system has at least one solution.

Inconsistent system has no solution.

Dependent solution has identical lines.

Independent systems has different lines.

We use method of elimination to solve this.

Adding -3y to both sides of eq(1), we have

x+3y-3y = 18-3y

x = 18-3y          eq(3)

put eq(3) into eq(2), we have

-(18-3y)+2y = 7

-18+3y+2y = 7

adding 18 to both sides of above equation , we have

18-18+3y+2y = 18+7

Adding like terms , we have

5y = 25

y = 5

Putting the value of y in eq(3), we have

x = 18-3(5)

x = 18-15

x = 3

Hence , the solution set is (3,5).

So, given system is consistent .

Their graphs are not same.so , their are independent.