Question

Solution q-2r=4
q+r=37

Answer 1

to solve these problems we can solve by substitution or elimination method. Now we use the method of elimination.

The first equation :
q - 2r = 4

second equation :
q + r = 37

now elimination equations 1 and 2

`q - 2r = 4\\\underline{q+~r= 37}~-\\~~-3r = -33\\~~~~~~~r = (-33)/(-3)\\~~~~~~~r = 11`

so the value of r is 11

now find the value of q by inserting r into equation 1

`q - 2r = 4\\q - 2(11)=4\\q - 22=4\\q=4+22\\q=26`

so the value of q is 26

So the value of :
r = 11
q = 26

Answer 2

q-2r=4, therefore: q=4+2r.

Plug the value of q into q+r=37, so you get:

4+2r+r=37

3r=37-4=33

3r=33

Therefore: r=11.

q-2r=4, but r=11, so:

q-2(11)=4

q-22=4

Therefore q=26.

Check if the answer is correct using second equation:

q=4+2r=4+2(11)=4+22=26.

So: q=26 and r=11.