Answer: 4
Step-by-step explanation:
3^2 + b^2 = 5^2
9 + b^2= 25
b^2 = 16
b = ±4
Answer: 7.7 years
Step-by-step explanation:
Given
The cost of HD TV is $700 and it is decreasing at the rate of 15% per year
After one year it becomes
![\Rightarrow 700-700\times 15\%\\\Rightarrow 700(1-0.15)](https://tex.z-dn.net/?f=%5CRightarrow%20700-700%5Ctimes%2015%5C%25%5C%5C%5CRightarrow%20700%281-0.15%29)
after 2 year it becomes
![\Rightarrow 700(1-0.15)-700(1-0.15)\times 15\%\\\Rightarrow 700(1-0.15)(1-0.15)\\\Rightarrow 700(1-0.15)^2](https://tex.z-dn.net/?f=%5CRightarrow%20700%281-0.15%29-700%281-0.15%29%5Ctimes%2015%5C%25%5C%5C%5CRightarrow%20700%281-0.15%29%281-0.15%29%5C%5C%5CRightarrow%20700%281-0.15%29%5E2)
Suppose, after x years it becomes $200
![\Rightarrow 200=700(1-0.15)^x\\\\\Rightarrow \dfrac{2}{7}=0.85^x\\\\\text{Taking log both sides}\\\\\Rightarrow x=\dfrac{\ln (\frac{2}{7})}{\ln (0.85)}\\\\\Rightarrow x=7.7\ \text{years}](https://tex.z-dn.net/?f=%5CRightarrow%20200%3D700%281-0.15%29%5Ex%5C%5C%5C%5C%5CRightarrow%20%5Cdfrac%7B2%7D%7B7%7D%3D0.85%5Ex%5C%5C%5C%5C%5Ctext%7BTaking%20log%20both%20sides%7D%5C%5C%5C%5C%5CRightarrow%20x%3D%5Cdfrac%7B%5Cln%20%28%5Cfrac%7B2%7D%7B7%7D%29%7D%7B%5Cln%20%280.85%29%7D%5C%5C%5C%5C%5CRightarrow%20x%3D7.7%5C%20%5Ctext%7Byears%7D)
Thus, it takes 7.7 years for the cost to come under $200.
Answer:
a
Step-by-step explanation:
Answer:
false
Step-by-step explanation:
Not all parallelograms are rectangles, only some of them are.
<span><span>The sum of a squared and b is given by
![a^2+b](https://tex.z-dn.net/?f=a%5E2%2Bb)
</span>7 times the sum of a squared and b is given by
</span><span>
while 4 times the sum of a squared and b is given by
</span>
![4(a^2+b)](https://tex.z-dn.net/?f=4%28a%5E2%2Bb%29)
Therefore, <span>7 times the sum of a squared and b minus 4 times the sum of a squared and b is given by
![7(a^2+b)-4(a^2+b)=3(a^2+b)](https://tex.z-dn.net/?f=7%28a%5E2%2Bb%29-4%28a%5E2%2Bb%29%3D3%28a%5E2%2Bb%29)
</span>