Answer:
![x = -7](https://tex.z-dn.net/?f=x%20%3D%20-7%20)
![y = - 12](https://tex.z-dn.net/?f=y%20%3D%20%20-%2012)
Step-by-step explanation:
The given system is:
4x-3y=8
5x-2y=-11
We make x the subject in the top equation to get:
![x = \frac{3}{4}y + 2](https://tex.z-dn.net/?f=x%20%3D%20%20%5Cfrac%7B3%7D%7B4%7Dy%20%2B%202)
Plug this expression for x in the bottom equation to get
![5( \frac{3}{4}y + 2) - 2y= - 11](https://tex.z-dn.net/?f=5%28%20%5Cfrac%7B3%7D%7B4%7Dy%20%2B%202%29%20-%202y%3D%20%20-%2011)
We expand to obtain
![\frac{15}{4} y + 10 - 2y = - 11](https://tex.z-dn.net/?f=%20%5Cfrac%7B15%7D%7B4%7D%20y%20%2B%2010%20-%202y%20%3D%20%20-%2011)
Multiply through by 4
![15y + 40 - 8y = - 44](https://tex.z-dn.net/?f=15y%20%2B%2040%20-%208y%20%3D%20%20-%2044)
Group similar terms
![15y - 8y = - 44 - 40](https://tex.z-dn.net/?f=15y%20-%208y%20%3D%20%20-%2044%20-%2040)
![7y = - 84](https://tex.z-dn.net/?f=7y%20%3D%20%20-%2084)
![y = - \frac{84}{7} =-12](https://tex.z-dn.net/?f=y%20%3D%20%20-%20%20%5Cfrac%7B84%7D%7B7%7D%20%20%3D-12%20)
This means
![x = -12\times \frac{3}{4} + 2](https://tex.z-dn.net/?f=x%20%3D%20%20-12%5Ctimes%20%20%5Cfrac%7B3%7D%7B4%7D%20%20%2B%202)
![x = - 7](https://tex.z-dn.net/?f=x%20%3D%20%20-%207)
Answer:
47.0
Step-by-step explanation:
In this right angle triangle, we are faced with a challenge of two sides. The opposite side and the adjacent side, hence the tangent is used.
Where it is the opposite side and hypothenus side, the sine is used and when it is the hypothenus side and adjacent side, the cosine is used.
Hence, we have tan62°=x/25
We cross multiply, to have
25(tan 62°)= x
x = 47.01816
In rounding up numbers, number 1 to 4 will be rounded up to zero, while numbers 5 to 9 will be rounded up to 1.
Rounding up 47.01816 to the nearest tenth. The tenth value is the figure is 0, before it we have 1, which is to hundredth. 1 will be rounded up to zero.
So we have 47.0
Answer:
30+(2x+7)+63=180(sum of angles of triangle )
30+2x+7+63=180
2x+100=180
2x=180-100
x=80/2
x=40
Answer:
Step-by-step explanation:
The interior angles of a heptagon add up to 5*180 = 900
So
x + 143 + 116 + 135 + 135 + 116 + 155 = 900 Add up the known angles
x + 800 = 900 Subtract 800 from both sides
x + 800 - 800 = 900 - 800 Combine
x = 100