Question 17
Linear and Simultaneous EquationsFind the values of x and y respectively if 3x − 5y + 5 = 0 and 4x − 7y + 8 = 0
- A.−5, −4
- B.−4, −5
- C.4, 5
- D.5, 4
Show the answer and explanation
Answer: D (5, 4)
Explanation
Multiply to get 12x − 20y = −20 and 12x − 21y = −24; subtracting gives y = 4. Then 3x = 20 − 5 = 15, so x = 5.