a) how to solve it by elimination method.

b) by substitution method
c) graphical method

I will show you A and B, and give you a hint how to do C, since doesn't provide C option.

A.

The elimination method is how I would solve this system

We start by multiplying the first equation by 3 and second by -2 to obtain

Now add the two equations and thus eliminate the x-terms to obtain

Then we insert the y into either of the original equations and solve for x

And we have the solution at .

B.

We pick one equation and express x

Then we replace the x in other equation with expression we just calculated and solve for y

Now we put y in either of the original equations to get x

And again we get the solution .

C.

To find solution graphically, you need to put both lines in general form where

Then plot the lines on the graph. The solution will be point where lines intersect, because we can represent lines as sets of points ordered pairs. Consider our two lines represented as two functions g and f where

Graphs (sets) of these two functions are defined as (assuming since not specified):

Where D is definition zone (set of all x defined for function f or g) and T transformation zone (set of all f(x) or g(x)). Note that in our case because

The solution is is intersection of these two sets

Hope this helps.

step-by-step explanation:

a. 12.5 kg

step-by-step explanation:

f = ma

so

m = f/a = (2500 n)/(200 m/s²) = 12.5 kg

1 n = 1 kg·m/s²