Answer: The correct option is (B) 1.1, -9.1.
Step-by-step explanation: We are given to solve the following quadratic equation by the method of completing the square.
In completing the square method, we need to make left hand side of the above given equation as a perfect square trinomial.
From equation (i), we have
Rounding to the nearest tenth, we get
Thus, the required solution is x = 1.1, -9.1.
Option (B) is CORRECT.
Anna is on holiday in Portugal.
She posts 15 postcards to the UK on Monday.
How many of her postcards can she expect to be delivered within a week?
(2 marks)
Answer:
You can expect at least 9 of her postcards to arrive within a week
To find that, we multiply the number of postcards by the probability
15 x 0.62 = 9.3
Hope this helps
Good Luck
The square root property seems to be another name for completing the square
x^2 + 5x + 6 = 0
We move the constant to the other side
x^2 + 5x = -6
We square half the linear coefficient and add that to both sides
x^2 + 5x + (5/2)^2 = -6 + 25/4
Now the left side is a perfect square,
(x + 5/2)^2 = 1/4
Here's the square root property part, we take the square root of both sides, remembering the ±
x + 5/2 = ± 1/2
x = -5/2 ± 1/2
Answer: x = -3 or x=-2
We check by plugging in these values to the original equation, and they work.
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x^2 + 6x = 16
Again we add half the linear coefficient, squared, to both sides
x^2 + 6x + 3^2 = 16 + 9
(x + 3)^2 = 25
Here comes the square root property, taking the square root of both sides:
x + 3 = ±5
x = -3 ± 5
x = 2 or x = -8
Again we check by substitution, and they both work
Answer: x = 2 or x = -8
Answer:
Amount needed by Zoya to meet her fundraising goal ≥ $ 300
Number of Bracelets possessed by Zoya = 100
Cost of single bracelet = $ 5
To meet her goal , we need to convert these statement into equation
Let number of Bracelets sold = x
1. x≤ 100
2. 5 x ≥ 300
Dividing both sides by 5, we get
x ≥ 60
The two inequality are : x ≤ 100 and x ≥ 60
So the inequality is : 60 ≤ x≤ 100.