A) 4 cm
B) 3 cm
C) 6 cm
D) 5 cm
Correct Answer: B
Solution :
If the altitude be \[x\] cm. then \[\frac{1}{2}\times (2x+2)x=12\] \[\Rightarrow \]\[(x+1)x=12\] \[\Rightarrow \]\[{{x}^{2}}+x-12=0\] \[\Rightarrow \]\[{{x}^{2}}+4x-3x-12=0\] \[\Rightarrow \]\[x(x+4)-3(x+4)=0\] \[\Rightarrow \]\[(x-3)(x+4)=0\] \[\Rightarrow \]\[x=3\] because \[x\cancel{=}-4\]You need to login to perform this action.
You will be redirected in
3 sec