It is 2.4 hours I hope this helped! :)
Step-by-step explanation:
![\text{Use}\ (a^n)^m=a^{nm}\\\\(2^3)^5=2^{3\cdot5}=2^{15}](https://tex.z-dn.net/?f=%5Ctext%7BUse%7D%5C%20%28a%5En%29%5Em%3Da%5E%7Bnm%7D%5C%5C%5C%5C%282%5E3%29%5E5%3D2%5E%7B3%5Ccdot5%7D%3D2%5E%7B15%7D)
Answer:
For the rectangle
Length=ℓ
Breadth=b
Area is 12 cm2
ℓb=12
Perimeter is 16 cm
2(ℓ+b)=16
ℓ+b=8
Substitute b=12ℓ from first equation
ℓ+12ℓ=8
ℓ2+12=8ℓ
ℓ2−8ℓ+12=0
Use quadratic formula (x=−b±√b2−4ac2a) to find ℓ
ℓ=−(−8)±√(−8)2−(4×1×12)2×1
ℓ=8±√162
ℓ=8±42
ℓ1=8+42=6
ℓ2=8−42
Step-by-step explanation:
For the rectangle
Length=ℓ
Breadth=b
Area is 12 cm2
ℓb=12
Perimeter is 16 cm
2(ℓ+b)=16
ℓ+b=8
Substitute b=12ℓ from first equation
ℓ+12ℓ=8
ℓ2+12=8ℓ
ℓ2−8ℓ+12=0
Use quadratic formula (x=−b±√b2−4ac2a) to find ℓ
ℓ=−(−8)±√(−8)2−(4×1×12)2×1
ℓ=8±√162
ℓ=8±42
ℓ1=8+42=6
ℓ2=8−42
From what I can see, you are on the right track.
one thing you could have done is combine like terms.
![{10}^{2} - {3}^{2} = {7}^{2}](https://tex.z-dn.net/?f=%20%7B10%7D%5E%7B2%7D%20%20-%20%20%7B3%7D%5E%7B2%7D%20%20%3D%20%20%7B7%7D%5E%7B2%7D%20)
Now just take the square root of 7 squared. That takes out the squared making your answer 7 or G.
You were on the right track, you just skipped a step.
hope this helped!