Will mark brainlist for anyone who answers these parts correctly and properly showed their work.

x=3, y=0

(3,0)

Step-by-step explanation:

-3x+ 5y = -9

4x+8y = 12

Divide the second equation by 4

x +2y = 3

Multiply this by 3

3x +6y = 9

Add this to the first equation

-3x+ 5y = -9

3x +6y = 9

0x + 11 y = 0

Divide by 11

11y/11 = 0/11

y =0

Now find x

x +2y = 3

x +2(0) =3

x=3

To solve this system of equations, I would use addition.

If you're going to solve a system of equations by addition,

both equations have to be in standard form.

Here, they both are in standard form so we can use addition.

Notice that we have a 5y in the first equation

and a 8y in the second equation.

If we multiply the 5y from the first equation by 8, that would give us 40y and if we multiplied the 8y in the second equation by -5, that would give us -40y.

So we would have a 40y and a -40y and our y terms would cancel.

So let's multiply our first equation by 8 to gives us our 40y and let's multiply our second equation by -5 to gives us our -40y.

Our first equation then becomes -24x + 40y = -72 and

our second equation becomes -20x - 40y = -60.

Now when we add our two equations together, our y's will cancel out.

-24x +  -20x is -44x and -72 + -60 is -132.

So we have -44x = -132.

Now dividing both sides by -44, we find that x = 3.

To solve for y, let's plug a 3 back in for x in our first equation

to get -3(3) + 5y = -9 or -9 + 5y = -9.

Adding 9 to both sides, we have 5y = 0 and dividing

both sides of the equation by 5, we find y = 0

So our answer is the ordered pair (3, 0).

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!