Answer:
1
Step-by-step explanation:
(-1) × (-1) × (-1) × (-1)
And - × - = +
+ × + = +
- × + = -
: = 1
25
so you replace all the x's with 15 and it becomes
2×15-5
2×15=30
30-5=25
Am sure boys are 13and girls also 13