Answer:
9y(2x - 1)(x - 2y)(x + 2y)
Step-by-step explanation:
Given
18x³y - 9x²y - 72xy³ + 36y³ ← factor out 9y from each term
= 9y(2x³ - x² - 8xy² + 4y²)
Factor the first/second and third/fourth term in the parenthesis
= 9y( x²(2x - 1) - 4y²(2x - 1)) ← factor out (2x - 1) from each term
= 9y(2x - 1)(x² - 4y²)
x² - 4y² is a difference of squares and factors in general as
a² - b² = (a - b)(a + b), thus
x² - 4y²
= x² - (2y)² = (x - 2y)(x + 2y), hence
18x³y - 9x²y + 72xy³ + 36y³
= 9y(2x - 1)(x - 2y)(x + 2y) ← in factored form
The answer is C, hope this helps
Answer:
#7: MK, LS and PR
#8: PN and PQ
#9: no
#10: no
Step-by-step explanation:
#7: lines MK, LS and PR are not intersecting each other, so these lines are parallel each other
#8: between lines PN and PQ is an right angle, so the lines PN and PQ are perpendicular
#9: lines PN and KM have an intesecting point, so they're not parallel
#10: there is no right angle between lines PR and NP
Rates like $ per channel is a slope, "m". The added fee is a constant so it's the intercept "b".
y = mx + b
So for the first problem (9)
(a)
y = total cost in dollars
x = number of premium channels
y = 16x + 44
(b) when x = 3 channels
y = 16(3) + 44
y = 92 $
the second problem (10)
(a) every 4 years the tree grows by 12-9=3 ft
So the unit rate or slope will be 3 ft per 4 yrs, (3/4). You can see this also by solving for slope "m" using the given points (4,9) and (8,12).
x = number of years
y = height of tree in ft
y = (3/4)x + b
use one of the points to find the y-intercept "b".
9 = (3/4)(4) + b
9 = 3 + b
9 - 3 = b
6 = b
y = (3/4)x + 6
(b) when x = 16
y = (3/4)(16) + 6
y = 12 + 6
y = 18 ft
