Using leaner combination method what is the solution to the system of linear equations 7x-2y=-20 and 9x+4y=-6

x = -2 and y = 3

Step-by-step explanation:

In linear combination method we try one of the variables from bopth of equations by

first making the variable equal in vlaue

then either subtracting or adding the two equation as required to eliminate the variable.

7x-2y=-20   equation 1

and 9x+4y=-6   equation 2

we see that y has

has value -2 and +4

4 = 2*2

thus, if we multiply equation1 with 2 we will give value for variable y as 4y and hence y can be eliminated easily.

7x-2y=-20  

multiplying the LHS and RHS with 2

2(7x-2y)=-20 *2

=> 14x - 4y = -40   eqaution 3

now that we have got 4y

lets add equation 2 and equation 3

  9x +4y=   -6

+14x - 4y = -40

=> 23x + 0 =  -46

x = -46/23 = -2

Thus, x = -2

substituitinng x = -2 in 7x-2y=-20

7*-2 -2y=-20

=> -14 -2y = -20

=> -2y = -20+14 = -6

=> y = -6/-2 = 3

Thus, y = 3

solution is x = -2 and y = 3

step-by-step explanation: