What must be added to
15x²-10x to make it
perfect square
a

Step-by-step explanation:

hello,

and we can write that

so

Then

then, I would say that you need to add 5/3 to make a perfect square

hope this helps

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6