Since a^2 - b^2 = 1, the value of y = 1 because x=1 and 1^2 - 1^2 = 0
Answer:
it's B
Step-by-step explanation:
It's definitely B
This form (x+b)²+c is a vertex form that can be found by completing square for the equation <span>x²+440x+440².
To complete square we will need to use formula a² +2ab + b² = (a+b)²
</span> x²+440x+440²,
<span>x² +2*220²x +220² -220² +440² (we added </span>220² -220², so nothing really changed here).
x² +2*220²x +220² -220² +440² ( here , bold part can be rewritten as (x+220)²)
(x+220)² -220² +440² (calculating bold part)<span>
</span>(x+220)² -220² +440² = (x+220)² + 145200
Now we have x²+440x+440², in the form that we need
x²+440x+440² = (x+220)² + 145200
(x+b)²+c = (x+220)² + 145200,
b=220,
c= 145200
So,
c/b = 145200/220 = 660
c/b = 660/1 (if you need it in a fraction form) or 660.
First, we need to find her current age. If she was 12 years old 3 years ago, her current age is 12 + 3 which is 15. If the ratio of Sarah's age to Keisha's age is 4:5 (Sarah's age is the 4 and Keisha's age is the 5).
If we take 15 and divide that by 5 (her ratio), then you get 3. Now multiply 3 by 4 to find Sarah's age. We get 12. Nine years from now, her age is 12 + 9 which is 21.
There is the answer. Sarah's age in 9 years is 21 years old. I hope this helps.
