For this case we must simplify the following expression:

We have that by definition of properties of powers that is fulfilled:

Then, rewriting the expression:

Answer:

-3 = x + x + x
-3 = 3x
-3/3 = x
x = -1
Here, (7 * 9) = (7 * 10) - (7 * x)
Here, Take 7 as a common factor according to distributive property:
= 7(10 - x)
Now, 10-x = 9
x = 10-9 = 1
In short, Your Answer would be 1
Hope this helps!
y = -2/3x + 5
this is the slope intercept. -2/3 is the slope and 5 is where it intercepts the y axis.
hope this helps