Answer:
29. (5,0) and (-7/2,0)
30. (-1,0) and (5/7,0)
Step-by-step explanation:
29. y=2x² - 3x - 35
y = (x-5)(2x+7)
y is 0 at x = 5 and -(7/2)
31: y=-7x² - 2x + 5
y = -(x+1)(7x-5)
y is 0 at -1 and 5/7
See the attached graph.
Answer:
Step-by-step explanation:
x-y=11
2x+y=19
---------------
x=y+11
2(y+11)+y=19
2y+22+y=19
3y+22=19
3y=19-22
3y=-3
y=-3/3
y=-1
x-(-1)=11
x+1=11
x=11-1
x=10
Answer: x=10, y=-1. (10, -1).
-----------------------------------------
-6x+5y=1
6x+4y=-10
-------------------
9y=-9
y=-9/9
y=-1
6x+4(-1)=-10
6x-4=-10
6x=-10+4
6x=-6
x=-6/6
x=-1
Answer: x=-1, y=-1. (-1, -1).
------------------------------------
2x+9y=25
-4x-9y=-23
-------------------
-2x=2
x=2/-2
x=-1
2(-1)+9y=25
-2+9y=25
9y=25-(-2)
9y=25+2
9y=27
y=27/9
y=3
Answer: x=-1, y=3. (-1, 3).
Answer:
It will take 3.2 hours for 8 inches of snow to fall.
Step-by-step explanation:
You can solve this be going "backwards".
You have 2.5 inches of snow falling per hour for x hours until you get 8 inches of snow, which can be represented like this:
2.5x=8 From here you being to solve by isolating x on one side of the equation. You would divide both sides by 2.5 to do this
2.5x=8
/2.5 /2.5
8 divided by 2.5 is 3.2 and you then get
x=3.2
It takes 3.2 hours for 8 inches of snow to fall
Answer:
The last one is the answer.
