Answer:
x = 2±sqrt(11)
Step-by-step explanation:
x^2 -4x - 7 =0
Add 7 to each side
x^2 -4x -7+7 =0+7
x^2 -4x =7
To complete the square take the coefficient of the x term and divide by 2 and then square it. Add it to both sides
-4 /2 = -2 then square
(-2)^2 = 4
Add 4 to both sides
x^2 -4x+4 =7+4
x^2 -4x+4 = 11
Factor the left side into (x-b/2)^2
(x-2)^2 =11
Take the square root of each side
sqrt((x-2)^2) =±sqrt(11)
x-2 = ±sqrt(11)
Add to to each side
x-2+2 = 2±sqrt(11)
x = 2±sqrt(11)
The answer to the problem is B.
Answer:
4x² -20x +61
Step-by-step explanation:
the quadratic equation can be written as (x-root1)(x-root2)
(x-(5/2) -3i) (x-(5/2)+3i), distribute
x² -(5/2)x +3xi -(5/2)x + 25/4 -(15/2)i -3xi +(15/2)i -9i², simplify
x² -(5/2)x -(5/2)x + 25/4 -9i², use the fact that i² =(√-1)² = -1 and substitute i²
x² -(5/2)x -(5/2)x + 25/4 +9, combine like terms and rewrite 9 as 36/4
x² -(10/2)x +25/4 + 36/4, combine like terms and simplify
x² -5x +61/4 is the quadratic expression yet it does not have integer coefficients so multiply by 4 to have all coefficients integers
4x² -20x +61
790 students I subtracted 1495-85 then divided that by two then added the 85 to 705 to get 790
Answer:
Step-by-step explanation:
The parameter in this hypothesis test describes the entire population. So in this test, the parameter is looking into the summary number for instance like an average of all overweights who after undergoing this pattern/daily habits exhibits weight loss.
