Question 423206
.
solving linear systems using substitution, what is
4x-7y=10
y=x-7
~~~~~~~~~~~~~~~~~~~~~~



        The solution in the post by @mananth is irrelevant, since it is done

        using the Elimination method, while the request was to use the Substitution method.


        I came to solve the problem as it is requested.



<pre>
Your starting equations are

    4x - 7y = 10    (1)
    y = x-7         (2)


Using equation (2), substitute y = x-7 in equation (1), replacing 'y' there

    4x - 7(x-7) = 10.


Simplify and find 'x'

    4x - 7x + 49 = 10

    49 - 10 = 7x - 4x

    39 =    3x

     x =     39/3 = 13.


Now from equation (2)  y = x - 7 = 13 - 7 = 6.


<U>ANSWER</U>.  x = 13,  y = 6.
</pre>

Solved as requested.