As we go from (-6,6) to (9,1), x increases by 15 and y decreases by 5. Thus, the slope of this line is m = rise / run = -5/15, or m = -1/3.
Point-slope form: y-6 = (-1/3)(x+6), using data from (-6,6).
Slope-intercept form: starting with y = mx + b, substit. -6 for x, 6 for y and -1/3 for m:
6 = (-1/3)(-6) + b, or
6 = 2 + b. Then b = 4, and the equation in slope-intercept form is
y = (-1/3)x + 4.
1. Use the FOIL method (x+9)(x+9)
First, outer, inner, last
Add your like terms
2. When you add or subtract polynomials you add or subtract the like terms and then put them in order from largest to smallest exponents.
3.
4. Since it is the perimeter, we add the 3 together.
Add the like terms together:
Put them in order of exponents
Hope this helps
<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
Combine like terms. Remember that like terms are terms that are completely the same excluding the coefficient.
7x-8x=-1x
Final answer: -x+5
First, find the probability of each event:
1) the probability that the spinner will land on a 7.
Since the spinner is split 4 equal sections and there is only 1 sector with 7, we can say the probability of getting a 7 is 1/4 as there is only 1 of 7 out of the total of 4 sections.
<em>and</em>
2) the probability that the spinner will land on B.
Since the spinner is split into 3 equal sections, and there is only 1 sector for B, we can say the probability of getting B is 1/3.
To find the probability of 2 events, we need to multiply the two probabilities.
1/4*1/3 = 1/12
So the answer is 1/12.