There is a lot to go over here. Unfortunately it looks like you got a lot incorrect. I'll focus on two problems. Hopefully these examples below will help correct the other mistakes.
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Problem 7)
We have the starting value be 20 and the ending value be 11. Subtract the values: (end)-(start) = 11 - 20 = -9. The negative indicates we have a drop or decrease.
We'll focus on the positive version of this number, so 9. Divide this value over the starting amount 20 to get 9/20 = 0.45 = 45%
So going from 20 miles to 11 miles is a decrease of 45%
Answer to problem 7 is: 45%
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Problem 13)
An increase of 300% means we added 3 times the original amount onto the original amount.
We take 300% of 25 to get 3*25 = 75
Which is then added onto 25 to get 25+75 = 100
Answer to problem 13 is: 100
4x-7=29 < do you understand how to set that up? Now, the goal is to “get x by itself.”
4x-7=29< now add the 7 to the 29. When you cross an equals sign you change the (+/-) sign of the number you’re moving.
4x= 36< now you will just divide by 4 on both sides. This will give you x by itself on the left side of the equals sign.
x=36/4 which is 9
X=9 :))
Given:
The wheel chair ramp is parallel to the ramp.
To find:
The value of x and y.
Solution:
If two lines are parallel, then the alternate interior angles are congruent.
4x° + 6y° = 86° --------- (1)
Similarly,
5x° + 6y° = 94°
Subtract 5x° from both sides.
5x° + 6y° - 5x° = 94° - 5x°
6y° = 94° - 5x° --------- (2)
Substitute (2) in (1).
4x° + 94° - 5x° = 86°
94° - x° = 86°
Subract 94° on both sides.
94° - x° - 94° = 86° - 94°
- x° = 86° - 94°
- x° = -8°
Multiply by -1 on both sides, we get
x = 8
Substitute x = 8 in (2).
6y° = 94° - 5(8)°
6y° = 54°
Divide by 6 on both sides, we get
y = 6
The value of x is 8 and y is 6.
Answer:
A≈12.57cm²
Step-by-step explanation:
A=1
4πd2=1
4·π·42≈12.56637cm²