Answer:
Step-by-step explanation:
x^2 - 2x - 15 = 0
(x - 5) (x + 3) = 0
x - 5 = 0
x = 5
x + 3 = 0
x = -3
Answer:
8
Step-by-step explanation:
If a dozen are 12 eggs then one third of 12 is 4 eggs. So two thirds is 2 times 4 eggs are 8 eggs.
Answer:
35,.......,..............
<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:
Step-by-step explanation:
Rewriting our equation with parts separated
Solving the whole number parts
Solving the fraction parts
Find the LCD of 8/9 and 2/3 and rewrite to solve with the equivalent fractions.
LCD = 9
Combining the whole and fraction parts
Hence, -1 7/9 is the correct Answer.
[RevyBreeze]