Answer: Yes, because they are similar triangles
Explanation:
Let ABC be the right triangle with vertical side of 3 and a horizontal side of 7.
And, right angle at B,
Then, AB = 3, BC = 7 ⇒ AC = √58
Again let, DEF be the right triangle with vertical side of 9 and a horizontal side of 21.
And, right angle at E,
Then, DE = 9, EF = 21 ⇒ DF = 3√58
Thus, in triangles ABC and DEF,
Therefore,
By the property of similar triangles,
Since, in both triangles horizontal sides BC and EF are on X-axis,
Therefore,
The second one is correct