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secondary 2 | Maths
2 Answers Below
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How do I do this question? I am unable to interpret what the question means and thus unable to solve it. I hope someone can reach out and help me out. I am in Sec 2. Also I hope that you can teach me and not give me the answer straightaway as I would like to learn how to do it so that I can attempt future questions like these myself. Thank you so much in advance :D
Date Posted: 3 years ago
Views: 571
The bracket (1,-1) mean x=1 and y=-1
Substitute these value to equation.
ie; 2(1) + 5(-1)
= 2 - 5
= -3
It is not a solution of the equation.
If the answer is -4 then is a solution of the equation.
Substitute these value to equation.
ie; 2(1) + 5(-1)
= 2 - 5
= -3
It is not a solution of the equation.
If the answer is -4 then is a solution of the equation.
b) x= -3 and y= 4
Substitute to equation
3(4)-4(-3)
= 12-(-12)
= 12+12
= 24
Is a solution of the equation.
Substitute to equation
3(4)-4(-3)
= 12-(-12)
= 12+12
= 24
Is a solution of the equation.
See 2 Answers
An ordered pair means a pair of x and y-values, with x on the left and y on the right. So for part a), that (1, -1) means x = 1, y = 1.
In the 2D Cartesian plane/graph where x-axis is the horizontal axis and y-axis is the vertical axis, this (1,-1) represents the coordinates of a point on the plane/graph.
2x + 5y = -4 actually can be rewritten as y = -2/5 x - 4/5, which is in the form of the equation of a straight line y = mx + c, where m is the gradient of the line and c is the y-intercept.
So, by asking you to determine if the ordered pair satisfies the equation, the question is basically asking you to check if this point (1,-1) lies on the line or not.
If it does, the ordered pair of values will satisfy the equation.
So now, all we have to do is to substitute x = 1, y = -1 into the equation.
2x + 5y = 2(1) + 5(-1) = 2 - 5 = -3
Now -3 ≠ -4, so the ordered pair does not satisfy the equation since the value on the left side of the equation does not equal the required -4 on the right side.
Therefore (1,-1) does not lies on the line 2x + 5y = -4
You can try b) on your own and let me know if you need more explanation.
In the 2D Cartesian plane/graph where x-axis is the horizontal axis and y-axis is the vertical axis, this (1,-1) represents the coordinates of a point on the plane/graph.
2x + 5y = -4 actually can be rewritten as y = -2/5 x - 4/5, which is in the form of the equation of a straight line y = mx + c, where m is the gradient of the line and c is the y-intercept.
So, by asking you to determine if the ordered pair satisfies the equation, the question is basically asking you to check if this point (1,-1) lies on the line or not.
If it does, the ordered pair of values will satisfy the equation.
So now, all we have to do is to substitute x = 1, y = -1 into the equation.
2x + 5y = 2(1) + 5(-1) = 2 - 5 = -3
Now -3 ≠ -4, so the ordered pair does not satisfy the equation since the value on the left side of the equation does not equal the required -4 on the right side.
Therefore (1,-1) does not lies on the line 2x + 5y = -4
You can try b) on your own and let me know if you need more explanation.
Correction : it should be x = 1 , y = -1 for the first part
Thank you so much!!
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