Answer:
The correct option is C
Step-by-step explanation:
if f(x)= x3 + x2 - 20x
Replace f(x) by y
y = x3 + x2 - 20x
0 =x3 + x2 - 20x
x3 + x2 - 20x = 0
Take out x as a common:
x(x2+x-20)=0
Find factors of x2+x+20.
x(x^2+4x-5x-20) = 0
x{x(x+4)-5(x+4)}=0
x(x+4)(x-5)=0
Set x= 0
x=0 , x+4=0 , x-5 =0
x=0, x=0-4 , x=0+5
x=0, x= -4, x=5
x=(0,5,-4)
The correct option is C....
Answer:
3
Step-by-step explanation:
18+18 = 36. 42-36 = 6. 6 / 2 = 3
Answer:
it should take her 45 minutes to run 9 laps
Step-by-step explanation:
40/8 = 5
9*5 = 45
How do you solve this system of equations using the addition method:
4
x
−
y
=
−
4
;
5
x
+
2
y
=
−
18
?
Algebra
1 Answer
IDKwhatName
Jun 30, 2017
x
=
−
2
,
y
=
−
4
Explanation:
Right now, you have:
4
x
−
y
=
−
4
5
x
+
2
y
=
−
18
To make this easier, you must get rid of one variable, in this case I will remove
y
, to do this you must make the y-values in both equations the same.
To do this, I will multiply the whole of
4
x
−
y
=
−
4
by 2 to give
8
x
−
2
y
=
−
8
We now have:
8
x
−
2
y
=
−
8
5
z
+
2
y
=
−
18
All we need to do now is
(
8
x
−
2
y
+
5
x
+
2
y
)
=
(
−
18
−
8
)
≡
13
x
=
−
26
.
Divide both sides by 13 to find
x
:
13
x
=
−
26
13
x
13
=
−
26
13
x
=
−
2
Now put your value for
x
into either equation:
4
(
−
2
)
−
y
=
−
4
−
8
−
y
=
−
4
y
=
−
8
+
4
y
=
−
4
x
=
−
2
;
y
=
−
4
Answer link
Answer:
Step-by-step explanation:
Move 3k to left hand side and change it's sign
Similarly, move 4.5 to right hand side and change it's sign
Collect like terms
Subtract 4.5 from 18
Divide both sides by 4.5
Calculate
Hope I helped!
Best regards! :D
