How do you write expressions in maths?

Abigail is a years old. Bob is b years old. Bob is older than Abigail. Write down, in terms of a and b, an expression for how many years older bob is than Abigail.

What is the question? Cause you could make a chart that might be easier. I dont know what the question is but you could represent Abigail as A and Bob as x and unknown as b.

so in the chart you could have bob and Abigail’s name down than the letter underneath it have the letters ( a and x). You could also have the known age for bob as b and known age for abigail is 1.

Depending on your question would be what sign you use and stuff. Anyways it might look something like this:

a1 * b= x

i dont know the proper sign cause the full question isnt there but i am pretty sure this is what your supposed to do. is this kinda what you are asking?

A stands for Abigail and ‘a’ is her age in years B stands for Bob and ‘b’ is his age in years x is the unknown difference in their ages:

A is ‘a’ B is ‘b’ b>a

x=b-a