Question

What is 3x-2y=11
X+2y=9 using substitution

Answer 1

Explanation:

`3x - 2y = 11 \\ 3x= 11 + 2y \\ x = (11 + 2y)/(3) ...........equation(i) \\ x + 2y = 9.......given \\ x = 9 - 2y .......equatiom(ii) \\ 9 - 2y = (11 + 2y)/(3) ......from \: equation \: i \: and \: ii \\ 27 - 6y = 11 + 2y \\ 16 = 8y \\ y = 2 \\ x = 5....putting \: the \: vaue \: of \: \: in \: equationi`

Answer 2

(5, 2)

Explanation:

We have hte equations:

3x - 2y = 11

x + 2y = 9

Solving by substituting simply means writing one variable in terms of the other, plugging that into the other equation, and then solving.

x + 2y = 9

x = 9 - 2y

Plug in 9 - 2y for x in the first equation:

3x - 2y = 11

3 * (9 - 2y) - 2y = 11

27 - 6y - 2y = 11

27 - 8y = 11

16 = 8y

y = 2

Use this to find x:

x = 9 - 2y = 9 - 2 * 2 = 9 - 4 = 5

The solution is (5, 2).