Respuesta :
y= - 1
The graph of the first line is 0. The graph of the second line will also be equal to 0. Replacing in the general equation of a line y=mx+c;
y=(0)x+c
y=c
Using the point (3,-1)
-1=c
y=-1
The graph of the first line is 0. The graph of the second line will also be equal to 0. Replacing in the general equation of a line y=mx+c;
y=(0)x+c
y=c
Using the point (3,-1)
-1=c
y=-1
Answer:
1 - [tex]y=-1[/tex]
2 - [tex]y=2x+4[/tex]
Step-by-step explanation:
The general form of a straight line is [tex]y=mx+b[/tex], where m = slope and b = y-intercept.
Ques 1: We are given that the line passes through (0,2.5) and (4,2.5).
Then the slope of the line is given by,
[tex]m=\frac{2.5-2.5}{4-0}=0[/tex]
Then, the y-intercept is given by,
[tex]y=0x+b\\\\2.5=b[/tex]
That is, the equation of the line is [tex]y=2.5[/tex]
Since, 'Two parallel lines have equal slope'.
Then, the line parallel to [tex]y=2.5[/tex] have slope 0 i.e. [tex]y=b[/tex].
As, the line passes through the point (3,-1) i.e. y= -1 for any value of x.
Then, the equation of line is [tex]y=-1[/tex]
So, option A is correct.
Ques 2: We are given that the line passes through (-2,0) and (0,-1).
Then the slope of the line is given by,
[tex]m=\frac{-1-0}{0+2}=\frac{-1}{2}[/tex]
Then, the y-intercept is given by,
[tex]-1=\frac{-1}{2}\times 0+b\\\\b=-1[/tex]
That is, the equation of the line is [tex]y=\frac{-1}{2}x-1[/tex]
Since, 'The product of slopes of two perpendicular lines is -1'.
Then, we have,
[tex]m\times \frac{-1}{2}=-1\\\\m=2[/tex]
The line perpendicular to [tex]y=\frac{-1}{2}x-1[/tex] have slope 2.
As, the line passes through the point (-1,2) with slope 2.
The y-intercept is given by,
[tex]2=2\times -1+b\\\\2=-2+b\\\\b=4[/tex]
Thus, the equation of the line is [tex]y=2x+4[/tex]
So, option A is correct.