Answer:
10
Step-by-step explanation:
there
<span>3x^2 + 4x + 8 + 2x^2 - 6x + 3 to give result as 9x^2 -2x - 5
</span>3x^2 + 4x + 8 + 2x^2 - 6x + 3
= 5x^2 - 2x + 11
so
9x^2 -2x - 5 - (5x^2 - 2x + 11)
= 9x^2 -2x - 5 - 5x^2 + 2x - 11
= 4x^2 -16
answer
expression (4x^2 -16) must be added to the sum of (3x^2 + 4x + 8) and (2x^2 - 6x + 3) to give the result as (9x^2 - 2x - 5)
Root4 < root7 < root9
2 < root7 < 3
14/5 = 2.8
root7 is an irrational number which is likely less than 2.8
Answer:
We know that the equation of the circle in standard form is equal to <em>(x-h)² + (y-k)² = r²</em> where (h,k) is the center of the circle and r is the radius of the circle.
We have x² + y² + 8x + 22y + 37 = 0, let's get to the standard form :
1 - We first group terms with the same variable :
(x²+8x) + (y²+22y) + 37 = 0
2 - We then move the constant to the opposite side of the equation (don't forget to change the sign !)
(x²+8x) + (y²+22y) = - 37
3 - Do you recall the quadratic identities ? (a+b)² = a² + 2ab + b². Now that's what we are trying to find. We call this process <u><em>"completing the square"</em></u>.
x²+8x = (x²+8x + 4²) - 4² = (x+4)² - 4²
y²+22y = (y²+22y+11²)-11² = (y+11)²-11²
4 - We plug the new values inside our equation :
(x+4)² - 4² + (y+22)² - 11² = -37
(x+4)² + (y+22)² = -37+4²+11²
(x+4)²+(y+22)² = 100
5 - We re-write in standard form :
(x-(-4)²)² + (y - (-22))² = 10²
And now it is easy to identify h and k, h = -4 and k = - 22 and the radius r equal 10. You can now complete the sentence :)
