<u>Question 8</u>
a^2 + 7a + 12
= (a+3)(a+4)
When factorising a quadratic, the product of the two factors should equal the constant term (12), and the sum of the two factors should equal the linear term (7). To find the two factors, list out the factors of 12 (1x12, 2x6, 3x4) and identify the pair that adds up to 7 (3+4).
An alternative method if you get stuck during your exam would be to solve it algebraically using the quadratic formula and then write it in the factorised form.
a = (-7 +or- sqrt(7^2 - 4(1)(12)) / 2(1)
= (-7 +or- sqrt(1))/2
= -3 or -4
These factors are the negative of the values that would go in the brackets when written in factorised form, as when a = -3 the factor (a+3) would equal 0. (If it were positive 3 instead, then in the factorised form it would be a-3).
<u>Question 10</u>
-3(x - y)/9 + (4x - 7y)/2 - (x + y)/18
Rewrite each fraction with a common denominator so you can combine the fractions into one.
= -6(x - y)/18 + 9(4x - 7y)/18 - (x + y)/18
= (-6(x - y) + 9(4x - 7y) - (x + y)) /18
Expand the brackets and collect like terms.
= (-6x + 6y + 36x - 63y - x - y)/18
= (29x - 58y)/18
= 29/18 x - 29/9 y
X =(-8+√464)/-8=1-1/2√<span> 29 </span><span>= -1.693</span>
Answer:
no escuche a estas personas en el sitio web, la mayoría son niños y no saben estas cosas
Step-by-step explanation:
Algunos de mis favoritos !!
Mi familia
Esposo, Kelly, de 25 años
Cuatro niños
Jessie, nuestra chiweenie
Equipos deportivos
Comida y bebida
Dulce
Color
Libros
Película
Aficiones
No me gusta
café
acostado
De fumar
Tocino
Trastorno
Bo
Falta de esfuerzo
Answer:
a)
b) 
c)
Step-by-step explanation:
Data given
x: 500, 700, 750, 590 , 540, 650, 480
y: 7.00, 7.50 , 9.00, 6.5, 7.50 , 7.0, 4.50
Part a
We want to create a linear model like this :

Wehre
And:
With these we can find the sums:
And the slope would be:
Nowe we can find the means for x and y like this:
And we can find the intercept using this:
And the line would be:
Part b
The correlation coefficient is given by:
For our case we have this:
n=7
The determination coefficient is given by:

Part c
Answer:
8.5 or 8½
Step-by-step explanation:
Arranged numbers in ascending order
2, 6, 8, 8, 9, 10, 12, 14
Median = middle number i. e 8 and 9
Therefore median = 8 + 9 divided by 2
= 17 divided 2
= 8.5
Answers = 8.5 or 8½