A) The line y = 4 meets the line 2x + y = 8 at the point A Fins the co-ordinates of A

b) The line 3x + y = 18 meets the x axis at the point B

Find the co-ordiantes of B

c) (i) Find the co-ordiantes of the mid-point M of the line joining A to B

(ii) Find the equation of the line through M parallel to 3x + y =18

answers :

a.

coordinates of A are (2,4)

b.

coordinates of B are (6,0)

i.

(4,2) is the midpoint

ii.

y = -3x + 18 is the parallel line

Step-by-step explanation:

a.

if two things are equal to the same thing then they are equal to each other

y = 4

2x + y = 8 is y = -2x +8 so

-2x +8 = 4

-2x = -4

x = 2

coordinates of A are (2,4)

b.

if two things are equal to the same thing then they are equal to each other

y=0

3x+y=18 is y = -3x+18 so

-3x+18=0

x = 6

coordinates of B are (6,0)

midpoint formula is

(X1+X2)/2 , (Y1+Y2)/2

(2,4) (6,0)

(X1+X2)/2 , (Y1+Y2)/2

(2+6)/2 , (4+0)/2

(4,2) is the midpoint

parallel line has the same x value

so for a line parallel to 3x+y=18 or y = -3x+18

the parallel line would be

y = -3x

point slope formula

point slope formulay - y1 = m (x - x1)

3x+y=18 or y = -3x+18 was 6,0 at y = 0

y - y1 = m (x - x1)

y - 0 = m (x - x1)

since it's a parallel line the m has to be the same

(6,0)

y - 0 = -3 (x - 6)

y = -3x + 18 is the parallel line

the answer is 45 i just did it on oddesy ware

a.   we have two

lines:   y = 4-x   and  

y = 8-x^-1

given two simultaneous equations that are both to be

true, then the solution is the points where the lines cross. the intersection is

where the two equations are equal. therefore the solution that works for both

equations is when

4-x = 8-x^-1

this is where the two lines will cross and that is the

common point that satisfies both equations.

b.   4-x = 8-x^-1

  x           4-x       8-x^-1

-3           7        

8.33

-2           6         8.5

-1           5         9

  0           4        

-

  1           3        

7

  2           2        

7.5

  3           1         7.67

the table shows that none of the x values from -3 to 3 is

the solution because in no case does

4-x = 8-x^-1

to find the solution we need to rearrange the equation to

find for x:

4-x = 8-x^-1

multiply both sides with x:

4x-x^2 = 8x-1

x^2+4x-1=0

x= -4.236, 0.236

therefore there are two points that satisfies the

equation.

find y:  

x=-4.236

y = 4-x   = 4 – (-4.236)

= 8.236

y = 8-x^-1 =   .236)^-1

= 8.236

x=0.236

  y = 4-x   = 4 – (0.236) = 3.764

y = 8-x^-1 =   8-(0.236)^-1

= 3.764

thus the two lines cross at 2 points:

(-4.236, 8.236) & (0.236, 3.764)

c.   to solve

graphically the equation 4-x = 8-x^-1

we would graph both lines: y = 4-x   and   y

= 8-x^-1

the point on the graph where the lines cross is the

solution to the system of equations.

just graph the points on part b on a cartesian coordinate

system and extend the two lines.   the

solution is, as stated, the point where the two lines cross on the graph.

step-by-step explanation:

mark brainliest!