Using substitution:
first you have to express one variable in terms of the other, in this we can express y in terms of x:

Since both expressions are equal to y, you have to equal both expressions like this:

Now you can solve the equation:

Knowing x=10, you can use any of the expressions we found before to find y. In this case I'm going to use y= -x+9 because it's simpler but boy should give you the same result

So, the answer is x=10 and y=-1
Answer:

Step-by-step explanation:

Use the pythagoream theorem to check. a^2+b^2=c^2
a=15 b=36 c= 39
225+1296=1521
The equation is true so it is a right triangle.
Answer:-44
Step-by-step explanation:
-16-(28)=-44
Answer: 2x(3x−1)(x+2)
Step-by-step explanation: