Answer:
7*5 + -29
Step-by-step explanation:
She makes 7 payments of 5 to the store
7*5
Then she gets 29 dollars back so that would be negative
+ -29
7*5 + -29
35 -29
She has paid 6 dollars to the store
Answer:
![\frac{dh}{dt}=\frac{30r}{\sqrt{d^{2}+900}}](https://tex.z-dn.net/?f=%5Cfrac%7Bdh%7D%7Bdt%7D%3D%5Cfrac%7B30r%7D%7B%5Csqrt%7Bd%5E%7B2%7D%2B900%7D%7D)
Step-by-step explanation:
A road is perpendicular to a highway leading to a farmhouse d miles away.
An automobile passes through the point of intersection with a constant speed
= r mph
Let x be the distance of automobile from the point of intersection and distance between the automobile and farmhouse is 'h' miles.
Then by Pythagoras theorem,
h² = d² + x²
By taking derivative on both the sides of the equation,
![(2h)\frac{dh}{dt}=(2x)\frac{dx}{dt}](https://tex.z-dn.net/?f=%282h%29%5Cfrac%7Bdh%7D%7Bdt%7D%3D%282x%29%5Cfrac%7Bdx%7D%7Bdt%7D)
![(h)\frac{dh}{dt}=(x)\frac{dx}{dt}](https://tex.z-dn.net/?f=%28h%29%5Cfrac%7Bdh%7D%7Bdt%7D%3D%28x%29%5Cfrac%7Bdx%7D%7Bdt%7D)
![(h)\frac{dh}{dt}=rx](https://tex.z-dn.net/?f=%28h%29%5Cfrac%7Bdh%7D%7Bdt%7D%3Drx)
![\frac{dh}{dt}=\frac{rx}{h}](https://tex.z-dn.net/?f=%5Cfrac%7Bdh%7D%7Bdt%7D%3D%5Cfrac%7Brx%7D%7Bh%7D)
When automobile is 30 miles past the intersection,
For x = 30
![\frac{dh}{dt}=\frac{30r}{h}](https://tex.z-dn.net/?f=%5Cfrac%7Bdh%7D%7Bdt%7D%3D%5Cfrac%7B30r%7D%7Bh%7D)
Since ![h=\sqrt{d^{2}+(30)^{2}}](https://tex.z-dn.net/?f=h%3D%5Csqrt%7Bd%5E%7B2%7D%2B%2830%29%5E%7B2%7D%7D)
Therefore,
![\frac{dh}{dt}=\frac{30r}{\sqrt{d^{2}+(30)^{2}}}](https://tex.z-dn.net/?f=%5Cfrac%7Bdh%7D%7Bdt%7D%3D%5Cfrac%7B30r%7D%7B%5Csqrt%7Bd%5E%7B2%7D%2B%2830%29%5E%7B2%7D%7D%7D)
![\frac{dh}{dt}=\frac{30r}{\sqrt{d^{2}+900}}](https://tex.z-dn.net/?f=%5Cfrac%7Bdh%7D%7Bdt%7D%3D%5Cfrac%7B30r%7D%7B%5Csqrt%7Bd%5E%7B2%7D%2B900%7D%7D)
<span>T = 3U / E solve for U
3U = T * E
U = (</span>T * E)/3
U = 1/3(TE)
Answer:
60
Step-by-step explanation:
I would assume you want the answer step-by-step:
We can count carefully and read the question again.
It is asking for us to count by tens or add ten to the most recent integer in the pattern.
In that case, we can see that our answer will by 50 + 10 = 60.
Also, note, that this question is not very intellectually challenging! Next time ask a question like "What do they mean when they say this?" If you don't understand the wording.