There's no answer, because there's no question.
The statement is an equation that describes a relationship between 'x' and 'y'. As a graph, the equation represents a straight line, with a slope of 2 and a y-intercept of -4.
If the question is "How much is Y ?", then 'x' must be given first. There are an infinite supply of pairs of numbers for 'x' and 'y' that make the statement true.
-2
y=8 y = 2x y = 2(4) <-- substitute 4 for x y = 8 <-- this is your answer
-6
2x-y=5, y=2x-5 4x+y=4, y=4-4x 2x-5=4-4x 6x=9 x=3/2 y= 2(3/2)-5 y=-2
x = 3 y = 4 2x + y - 1 = (6) + (4) - 1 = 9
-2
y=2x-4 y=2x-5 y=1 1=2x-4 -2x = -5 x=2/5 the solution is (x,y) = (2/5,1)
6
y=8 y = 2x y = 2(4) <-- substitute 4 for x y = 8 <-- this is your answer
2x-y = 4 -y = -2x+4 y = 2x-4 in slope-intercept form
2x + 4 = y ...............2x + 4 = y ....................2x + 4 = y .............2*(-6)+ 4 = y x - y = 2 .......<=> ...x - 2x - 4 = 2 .....<=> ...x = -6......... <=>.... x = -6 ..............<=> y = - 8 x = - 6
-6
2x-y=5, y=2x-5 4x+y=4, y=4-4x 2x-5=4-4x 6x=9 x=3/2 y= 2(3/2)-5 y=-2
x = 3 y = 4 2x + y - 1 = (6) + (4) - 1 = 9
If: y = -2x+4 and y = 23x-4 Then: -2x+4 = 23x-4 And: -25x = -8 So: x = 0.32 and by substituting y = 3.36 Intersection: (0.32, 3.36)
Given y = 2x + 4, plug in x = 42 and simplify: y = 2(42) + 4 y = 84 + 4 y = 88
-2