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y=3x+4 -3x+y=4 x=-1/3
Their graphs are.
3x - y = -4 3x - y = 0 Those lines do not intersect. They are parallel. You can demonstrate by solving either of them for one of the two variables, then plugging it's value into the other: 3x - y = -4 ∴y = 3x + 4 Now substitute: 3x - y = 0 ∴ 3x - (3x + 4) = 0 ∴ 3x - 3x - 4 = 0 ∴ -4 = 0 This result is obviously incorrect, indicating that the lines do not intersect.
y = 1/3x+4
y = 3x + 1 y = 3x + 2 y = 3x + 3 y = 3x
3x - y = 4 Get y by itself to see if it is the same as y = 3x - 4: 3x = 4 + y 3x - 4 = y Therefore, 3x - y = 4 is the equivalent of y = 3x - 4.
y = 3x = 12y = 12
y = 3x - 4 y = 4 + x Subtract the second equation from the first: y - y = 3x - 4 - 4 - x 0 = 2x - 8 2x = 8 so that x = 4 Substitute for x into second equation: y = 4 + 4 = 8 So the solutions is (4, 8).
y=3x+4 -3x+y=4 x=-1/3
Their graphs are.
7
y = 12. It's the transitive property. y = 12 = 3x.
3x - y = -4 3x - y = 0 Those lines do not intersect. They are parallel. You can demonstrate by solving either of them for one of the two variables, then plugging it's value into the other: 3x - y = -4 ∴y = 3x + 4 Now substitute: 3x - y = 0 ∴ 3x - (3x + 4) = 0 ∴ 3x - 3x - 4 = 0 ∴ -4 = 0 This result is obviously incorrect, indicating that the lines do not intersect.
y = 1/3x+4
y = 3x + 1 y = 3x + 2 y = 3x + 3 y = 3x
So -3x - 6 = x - 4, ie -2 = 4x so x = -½ and y = -4½
4