Maria is 10 years older than Zohar. The sum of their ages 23. Which equation would represent this scenario?

Since Zohar is 6 1/2, Maria must be 16 1/2.

Explanation:

There are two equations, but they can be collapsed into one (and solved!):

M = Z + 10

M + Z = 23

(Z+10) + Z = 23 <<< this equation represents the stated problem, with one unknown

2Z = 13 <<< simplified

Z = 13/2 = 6 1/2 <<< solved (it is very unusual for age problems to have fractional answers)