Answer: x=9
Step-by-step explanation:
x^2-8x-9=0...
we can simplify this by adding 9 to each side... so it turns into this: x^2-8x=9
Then, we can turn x^2 to x*x because we know that anything to the power of two is itself multiplied by itself. So our new equation will be this:
x*x-8x=9
Now we know x has to be 9 because 8 is 1 less than 9. Therefore, our answer would be x (9)...
Let’s test this out... first, let’s substitute x with the number 9:
9^2-8*9-9=0. Simplify this:
81-72-9=0. We can then simplify furthers and we get:
0=0. This means that the equation is true
