The sides of one triangle are 4 cm, 6 cm and 7 cm, the smaller side of a similar triangle is 12 cm. Find the other sides of the triangle.

The smaller side of the second triangle is correspondingly similar to the smaller side of the first triangle, which means:
Side 2 of a 12 cm triangle is similar to side 1 of a 4 cm triangle
Let’s calculate the coefficient of similarity k = 12/4 = 3
k = 3
So, to find the remaining sides of the 2 triangle, you need to multiply each side of the 1 triangle by the similarity coefficient k
So the other sides will be respectively equal:
6 * 3 = 18cm
7 * 3 = 21 cm
Answer 18, 21 cm