Respuesta :
Answer:
D) (2, -1)
Step-by-step explanation:
12x - y = 25
9x + y = 17
21x = 42
x = 2
Plug 2 in for x to find y
18 + y = 17
y = -1
(2, -1)
Explaination :
Here we have been given with two equations and we have to use elimination method to solve them and get the value of x and y respectively.
- 12x - y = 25 (Equation No 1)
- 9x + y = 17 (Equation No 2)
• In Equation No 2 :
Transposing the 9x which is in L.H.S. to R.H.S. it would be negative.
⇒ y = 17 - 9x
• In Equation No 1 :
We will substitute the temporary value of y which we got above here.
⇒ 12x - y = 25
⇒12x - (17 - 9x) = 25
⇒ 12x - 17 + 9x = 25
⇒ 12x + 9x - 17 = 25
⇒ 21x - 17 = 25
⇒ 21x = 25 + 17
⇒ 21x = 42
⇒ x = 42 / 21
⇒ x = 14 / 7
⇒ x = 2
Therefore,
- Value of x is 2.
★ Finding out value of y :
⇒ y = 17 - 9x
⇒ y = 17 - 9(2)
⇒ y = 17 - 9 × 2
⇒ y = 17 - 18
⇒ y = -1
Therefore,
- Value of y is -1
★ Henceforth,
- Option D (2 , -1) is correct.
Learn More :
https://brainly.com/question/27418556