Dear @dorismos

Thank you for participating in Steemit Math Class and for completing the Activity task for the week. You got 9.5/10 Grade Points according to the following Scale;

Criteria	Marks
Question 1	3/3
Question 2	2.5/3
Question 3	2/2
Content Quality	2/2
Total	9.5/10

Comment:

• Your answers are right, but you made a mistake while solving question 2. You wrote

Divide both sides by -1
-y/-1 = 8 - x/-1
y = -8-x

If you divide the right side by -1 you should have obtained

y = -8 + x

Because the minus is for both 8 and -x.

This would have save you from the trouble I'm sure you had here while solving.

Substituting -8-x for y in equation 1
x+(-8-x)=7
x-8-x=7

Here if I collected right terms, it's x-x=15, which it wrong.

But by subsituting y = -8 + x instead you should have obtained.

x+(-8+x)=7
x-8+x=7
2x=15

We appreciate your efforts and look forward for your next homework tasks.

Best Regards
@whileponderin