Question

(08.03)A system of equations is given below:

y = –2x + 1
6x + 2y = 22

Which of the following steps could be used to solve by substitution?
6x + 2(−2x + 1) = 22
−2x + 1 = 6x + 2y
6(−2x + 1) + 2y = 22
6(y = −2x + 1)

Answer 1

hello :
y = –2x + 1 ....(1)
6x + 2y = 22 ....(2)
by substitution in (2) : 6x+2(-2x+1) =22
6x-4x+2 = 22
2x =20
x =10
in(1) : y =-2(10)+1 = -19

Answer 2

6x + 2(−2x + 1) = 22

Explanation:

The given equations are :

`y =-2x+1` ....(1)

`6x+2y=22` ....(2)

Substitution means, putting in the values of x or y in the second equation.

We have been given the value of 'y' (1) so we will put that in place of 'y' in the (2) equation.

`6x+2(-2x+1)=22`

So, we can solve it further.

`6x-4x+2=22`

`2x=22-2`

`2x=20`

`x=10`

And
`y =-2(10)+1`

`y =-20+1`

`y =-19`

So, the 1st option is the right answer: 6x + 2(−2x + 1) = 22