Step-by-step explanation:
4. : Multiplication Equality
Addition Equality
Check:
![5 - 2y = 19](https://tex.z-dn.net/?f=5%20-%202y%20%3D%2019)
![- 2y = - 14](https://tex.z-dn.net/?f=%20-%202y%20%3D%20%20-%2014)
![y = 7](https://tex.z-dn.net/?f=y%20%3D%207)
5.
Division Equality
Multiplication Equality
Subtraction Equality
Check:
![\frac{5m}{4} - 3 = - 13](https://tex.z-dn.net/?f=%20%5Cfrac%7B5m%7D%7B4%7D%20%20-%203%20%3D%20%20-%2013)
![\frac{5m}{4} = - 10](https://tex.z-dn.net/?f=%20%5Cfrac%7B5m%7D%7B4%7D%20%20%3D%20%20-%2010)
![5m = - 40](https://tex.z-dn.net/?f=5m%20%3D%20%20-%2040)
![m = - 8](https://tex.z-dn.net/?f=m%20%3D%20%20-%208)
6.
Multiplication Equality
Addition Equality
Division Equality
Check:
![\frac{ - 25r + 13}{4} = - 3](https://tex.z-dn.net/?f=%20%20%5Cfrac%7B%20-%2025r%20%2B%2013%7D%7B4%7D%20%20%3D%20%20-%203)
![- 25r + 13 = - 12](https://tex.z-dn.net/?f=%20-%2025r%20%2B%2013%20%3D%20%20-%2012)
![- 25r = - 25](https://tex.z-dn.net/?f=%20-%2025r%20%3D%20%20-%2025)
![r = 1](https://tex.z-dn.net/?f=r%20%3D%201)
8.
t=3,. Given
![3t = 9](https://tex.z-dn.net/?f=3t%20%3D%209)
Justification: Multiply both sides by 3
Step 2:
![3t + 50 = 59](https://tex.z-dn.net/?f=3t%20%2B%2050%20%3D%2059)
Add 50 to both sides.
Step 3:
![\frac{3t + 50}{4} = \frac{59}{4}](https://tex.z-dn.net/?f=%20%5Cfrac%7B3t%20%2B%2050%7D%7B4%7D%20%20%3D%20%20%5Cfrac%7B59%7D%7B4%7D%20)
Divide both sides by 4.
Check
![\frac{3t + 50}{4} = \frac{59}{4}](https://tex.z-dn.net/?f=%20%5Cfrac%7B3t%20%2B%2050%7D%7B4%7D%20%20%3D%20%20%5Cfrac%7B59%7D%7B4%7D%20)
![3t + 50 = 59](https://tex.z-dn.net/?f=3t%20%2B%2050%20%3D%2059)
![3t = 9](https://tex.z-dn.net/?f=3t%20%3D%209)
![t = 3](https://tex.z-dn.net/?f=t%20%3D%203)
Answer:
I would say B but i can be wrong, its math all it is is just a puzzle.
Step-by-step explanation:
First, we need to find the area of wall we need to cover. The room is 10 by 12 by 8 feet. I'm assuming that we only need to wallpaper the ceiling and side walls. It would be weird to wallpaper the floor when there is carpet/tiling.
Ceiling area: ![10 \times 12 = 120](https://tex.z-dn.net/?f=10%20%5Ctimes%2012%20%3D%20120)
Wall area: ![2(12 \times 8)+2(10 \times 8)=352](https://tex.z-dn.net/?f=2%2812%20%5Ctimes%208%29%2B2%2810%20%5Ctimes%208%29%3D352)
Total area: ![120+352=472](https://tex.z-dn.net/?f=120%2B352%3D472)
Now, we subtract 15 feet for each window and door. There are two windows and two doors.
![472-4(15)=412](https://tex.z-dn.net/?f=472-4%2815%29%3D412)
412 square feet of wall needs to be wallpapered. Dividing this by 70 (the square footage covered by one roll) gives something a little less than 6.
6 full rolls of wallpaper will be needed to fully wallpaper the room.
Answer:
5x-2
Step-by-step explanation:
15x^2-x-2
15x^2+5x-6x-2
factorize
5x(3x+1)-2(3x+1)
Sol: (3x+1)*(5x-2)