<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
Answer:
UNIF(2.66,3.33) minutes for all customer types.
Step-by-step explanation:
In the problem above, it was stated that the office arranged its customers into different sections to ensure optimum performance and minimize workload. Furthermore, there was a service time of UNIF(8,10) minutes for everyone. Since there are only three different types of customers, the service time can be estimated as UNIF(8/3,10/3) minutes = UNIF(2.66,3.33) minutes.
Answer:
1. x= 8
2. x= 6
3. x= 7
4. x= -8
Code: BECI
Step-by-step explanation:
(1 & 2/3) ft = (1 ft) + (2/3 ft)
(1 & 2/3) ft = 12 inches + 12*(2/3) inches
(1 & 2/3) ft = 12 inches + 8 inches
(1 & 2/3) ft = 20 inches
If the tree grows 5 inches per year, then it will take 4 years to get to 20 inches since 5*4 = 20. You can also divide to get 20/5 = 4.
So it takes 4 years for the tree to grow 1&2/3 feet tall.
If
is left, that means
was spent. So
of the total amount is equal to 39.. Let's say x to the total amount.
