The line equation is Y= - 1/2x +4
<span>Let b= speed of boat in still water
Let c= speed of current
Upstream
Speed is ; b-c
d u=(b-c)* t u
Downstream
speed is ; b+c
d d=(b+c)*t d
given:
d u=18
t u=3
d d=24
t d=2
------------------
(1) 18=(b-c)*3
(2) 24=(b+c)*2
and
(1) 18=3b-3c
(2) 24=2b+c
Multiply both sides of (1) by 2
Multiply both sides of (2) by 3
(1)
(2)
Add (1) and (2)
And, from (1),
18=3*9-3c
3c=27-18
3c=9
c=3
The speed of the boat in still water is 9 mi/hr
The speed of the current is 3 mi/hr
check:
(1) 18=(9-3)*3
(2) 24=(9+3)*2
and
(1) 18=16*3
18=18
(2) 24=24
</span>
Answer:
3x² - 12x - 36
= 3(x - 6)(x + 2)
Step-by-step explanation:
3x² - 12x - 36 Find any common factor. All terms are divisible by 3.
= 3(x² - 4x - 12) Find two numbers that sum to -4 and whose product is -12. Replace -4 with these two numbers.
= 3(x² - 6x + 2x - 12) Group the terms splitting from the middle
= 3( (x² - 6x) + (2x - 12) ) Find the common factor in each group.
= 3( x(x - 6) + 2(x - 6) ) The groups have a common factor (x - 6).
= 3( (x - 6)(x + 2) ) Remove the extra brackets
= 3(x - 6)(x + 2) Fully factored
