What is the rest of the problem? I can help you!
Answer:
You stopped at 2y-4=12
If we add same number to both sides the equation will remain true. For example if we have 5=5, and we add 7 to both sides, we get 12=12 which is also true. Now let's do this with our equation. Add 4 to both sides(to have only y on the left side). We get 2y=16, hence y=8.
Answer. 2y=16
The first pipe pumps out
while the second pipe pumps out
So together, both pipes pump out
That is, with both pipes filling the tank, it should take 32 minutes total.
Answer:
6)
a. x=35
b. x=4
c. x=30
Step-by-step explanation:
6a) 7/9=x/45
7/9×45=x
7×45/9=x
315/9=x
35=x
x=35
————————
b. 10/8=5/x
5/4=5/x
5/4x=5(the x is in the middle of the division sign here)
5x/4=5(the x is NOT in the middle of the division sign)
5x=5×4
5x=20
x=20/5
x=4
———————
c. x/34=15/17
x=15/17×34
x=15×34/17
x=510/17
x=30
hope that helped you. I can't answer number 7, I'm sorry
f
'
(
x
)
=
1
(
x
+
1
)
2
Explanation:
differentiating from first principles
f
'
(
x
)
=
lim
h
→
0
f
(
x
+
h
)
−
f
(
x
)
h
f
'
(
x
)
=
lim
h
→
0
x
+
h
x
+
h
+
1
−
x
x
+
1
h
the aim now is to eliminate h from the denominator
f
'
(
x
)
=
lim
h
=0
(
x
+
h
)
(
x
+
1
)−
x
(
x
+
h
+
1)
h
(
x
+
1
)
(
x
+
h
+
1
)
f
'
(
x
)
=
lim
h
→
0
x
2
+
h
x
+
x
+
h
−
x
2
−
h
x
−
x
h
(
x
+
1
)
(
x+h
+
1
)
f
'
(
x
)
=
lim
h
→
0
h
1
h
1
(
x
+
1
)
(
x
+
h
+1
)
f
'
(
x
)
=
1
(
x
+
1
)
2
