Question

4x + 3y=11
2x-5y= 25
Using substitution

Answer 1

By using substitution method, make x the subject. So 4x+3y=11 , x=11/4 - 3/4y
Hence, substitute x=11/4 - 3/4y into 2x-5y=25. Hence solve for y (ans: -3)
Therefore use y=-3 to substitute into x=11/4 - 3/4y = 5. Final Answer : x=5,y=-3. Hope this helps but I would suggest you consider elimination method as it is much easier for you to solve this.

Answer 2

(5, - 3 )

Explanation:

4x + 3y = 11 → (1)

2x - 5y = 25 ( add 5y to both sides )

2x = 25 + 5y → (2)

note that 4x = 2(2x)

substitute 2x = 25 + 5y into (1)

2(25 + 5y) + 3y = 11

50 + 10y + 3y = 11

13y + 50 = 11 ( subtract 50 from both sides )

13y = - 39 ( divide both sides by 13 )

y = - 3

substitute y = - 3 into (2)

2x = 25 + 5(- 3) = 25 - 15 = 10 ( divide both sides by 2 )

x = 5

solution is (5, - 3 )