please answer all question number wise
Answers
Answer:
25.) (d) None of these
26.) (d) None of these
27.) (a) 0x + y - 2 = 0
28.) (b) x = 1, y = 2
29.) (d) xy = 2x + 1
Step-by-step explanation:
25.) Every equation written here is a linear equation. So the answer is (d) None of these.
26.) For x = 0,
4×0 + 3y = 12
⇒ 3y = 12 - 0
⇒ 3y = 12
⇒ y = 12/3
⇒ y = 4
So (0,4) is a solution.
For x = 1,
4×1 + 3y = 12
⇒ 3y = 12 - 4
⇒ 3y = 8
⇒ y = 8/3
So (1,8/3) is a solution.
For x = 2,
4×2 + 3y = 12
⇒ 3y = 12 - 8
⇒ 3y = 4
⇒ y = 4/3
So (2,4/3) is a solution.
For x = 3,
4×3 + 3y = 12
⇒ 3y = 12 - 12
⇒ 3y = 0
⇒ y = 0/3
⇒ y = 0
So (3,0) is a solution.
Four solutions are: (0,4); (1,8/3); (2,4/3); (3,0).
As there is no option like "4 solutions", the answer is (d) None of these.
27.) In (a), 0x + y - 2 = 0
=> y - 2 = 0
This satisifies the question's condition.
Thus, the answer is (a) 0x + y - 2 = 0.
28.) (a) x = 2, y = 2
Putting in x + 2y = 6,
=> 2 + 2(2) = 6
=> 2 + 4 = 6
=> 6 = 6 This is a solution of x + 2y = 6 as LHS = RHS.
(b) x = 1, y = 3
Putting in x + 2y = 6,
=> 1 + 2(3) = 6
=> 1 + 6 = 6
=> 7 = 6 which is not possible. Thus, x = 1, y = 3 is not a solution of x + 2y = 6.
Thus, the answer is (b) x = 1, y = 3.
29.) For a line to pass through the origin, x and y should be 0.
(a) x + y = 0
Putting x = y = 0,
=> 0 + 0 = 0
=> 0 = 0 This line will pass through the origin.
(b) y = 2x
=> 0 = 2(0)
=> 0 = 0 This line will pass through the origin.
(c) y = x
Putting x = y = 0,
=> 0 = 0 This line will pass through the origin.
(d) y = 2x + 1
Putting x = y = 0,
=> 0 = 2(0) + 1
=> 0 = 0 + 1
=> 0 = 1 which is not possible. Thus, this line will not pass through the origin.
Thus, our answer is (d) y = 2x + 1.