Consider two triangles ABC and ABD with internal angles as shown and a...
Steps 1 & 2: Understand Question and Draw Inferences
Here we can see that triangles ABC and ABD form the special triangles 30°-60°-90° and 45°-45°-90° respectively.
And we know that:
i) In a 30°-60°-90° triangle, the sides opposite to the angles 30°, 60°, and 90° respectively are in the ratio 1 : √3 : 2
ii) In a 45°-45°-90° triangle, the sides opposite to the angles 45°, 45°, and 90° respectively are in the ratio 1 : 1: √2
Let’s assume the length of side BC to be x units.
The lengths of all the other sides of the two triangles can be calculated in terms of x by applying the above ratios. The result will be as shown:
Thus, in order to find the length of AC, we need to find the value of x.
Step 3: Analyze Statement 1
AD2+AC2=1000
This means
(√6x)2+(2x)2=1000
6x2+4x2=1000
10x2=1000
x2=100
x=10
(The negative value of x is rejected because x, being the length of a geometrical figure, cannot be negative)
Since we know the value of x, we will be able to find the length of AC.
Thus, Statement 1 alone is sufficient.
Step 4: Analyze Statement 2
CD=10(√3+1)
This means,
x+3√x=10(3√+1)
x(1+√3)=10(√3+1)
x=10
Since we know the value of x, we will be able to find the length of AC.
Thus, Statement 2 alone is sufficient
Step 5: Analyze Both Statements Together (if needed)
We do not need to analyze further as both statements (1) and (2) are sufficient.
Answer: Option (D)