X-3y=18
X always has a 1 in front of it so
1x-3y=18
-1x -1x You will have to get -3y by its self.
-3y=-1x + 18 when you move 1x over the = it turns into a -1x
/-3 /-3 /-3 divided everything by -3 to get y by its self
Y= 1/3 - 6 and that is you answer
In the standard form of quadratic

the discriminant is

In your quadratic, a = 1, b = -9 and c = -10
Now you need to plug these values into the expression for the discriminant.
I would use the pythagorean theorem to find the lengths of each side. a² + b² = c².
Side AB is one we're looking for. If you make other right triangle with that same side you can see that one length is 4 and the other is 3. So, 4² + 3² = c² → 25 = c² → 5 = c. Side AB is length 5.
Side AC is another. Do the same with that side and you get that one length is 4 and the other is 3. (This is the same one as above) so side AC is length 5.
Side BC is the last one. One of the lengths is 1 and the other is 1 → 1² + 1² = c² → 2 = c² → 1.414213562 = c so side BC is approximately length 1.41.
Add each length up and you get a perimeter of roughly 11.4
14 apples because altogether the ratio adds up to 7 and 49/7=7 so we could rewrite the ratio as 2x:5x so x=7. there for 2x ,the number of apples is 14
The ladder resting against the house forms a triangle similar to the one in the image below
To answer this question you must use Pythagorean theorem

a and b are the legs (the sides that form a perpendicular/right angle)
c is the hypotenuse (the side opposite the right angle)
In this case...
a = x
b = 4
c = 20
^^^Plug these numbers into the theorem

solve for x
+ 16 = 400
= 384
x = 8√6
or
x ≈ 19.5959....
Hope this helped!
~Just a girl in love with Shawn Mendes