I believe what the problem means is that the height of the child, if he/she grows in height, the mesurements are equal to 1 ft, 2 ft, 3 ft, 4 ft, etc only. and no decimals or fractions in between. it is also said that a human stops growing at the age of 20 naturally, hence with this increment, a child can grow incredibly very tall.
The irrational number that can be added to pi to get a rational sum is PI.
You can solve this by using "similar triangles".
In triangle ABC, we are looking for side AC which is x. Side AC is similar to side DF in triangle EDF.
You can solve for side x by picking two sides in triangle ABC and their corresponding sides in triangle EDF. This is what I mean:

Substitute for the values of AC, BC, DF and EF:


To solve for y, do the same thing. Pick two sides on triangle ABC and their corresponding sides in triangle DEF.

Substitute for the values and solve:


We have the value x to be 5.5 units and y to be 6 units.
Answer:
c
Step-by-step explanation:
Multiply 9 by 2a and 2, and you get 18a + 18. Another equivalent expression would be 18(a+1), which you can get by factoring the above answer.