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Math problems in the eighth grade
(1) The straight line L is parallel to the known straight line y=-2x- 1, so the linear coefficient is -2, and the resolution function can be obtained according to the undetermined coefficient method.

(2) The coordinates of point A and point B can be found, and the position of point C can be discussed on the left and right sides of point B. The coordinates of point C can be found according to the area of triangle. Solution: Solution: (1) Let the functional expression of the straight line L be y=kx+b,

∫ The line L is parallel to the line y=-2x- 1, ∴k=-2.

∫ The straight line L passes through the point (1, 4),

∴-2+b=4,

∴b=6.

The functional expression of the straight line L is y =-2x+6.

The image of the straight line l is shown in the figure.

(2) The straight line L intersects the Y axis and the X axis at points A and B respectively.

∴ The coordinates of point A and point B are (0,6) and (3,0) respectively.

∫l∨m,

∴ The straight line m is y =-2x+T Let y=0 and get x=? ,

∴ The coordinates of point C are (? ,0).

∵t>0,∴? >0.

The point ∴C is on the positive semi-axis of the X axis.

When point C is to the left of point B, S=? ×(3-? )×6=9-? ;

When point C is to the right of point B, S=? ×(? -3)×6=? -9.

∴△∴△abc's functional expression about the area s of T is S=