Answer:
4 days
Step-by-step explanation:
June starts on Monday
for 30days we have 4 weeks starting from Monday to Sunday and extra 2 days which are Monday and Tuesday
so we have 5 mondays and tuesdays
4 wed, thu, fri, sat, sun
Aliza played piano on june1 monday
So aliza played basketball on 5 tues + 4 thurs = 9 days
for calculating both basketball and paino
piano day should be on tuesday or thursday
from the below picture u can see pink dots are piano days
and yellow circles are both piano and basketball days
so on alternate weeks they are coinciding
so there are 4 days
 
        
             
        
        
        
Simplifying
8x + -6 = 7x + 10
Reorder the terms:
-6 + 8x = 7x + 10
Reorder the terms:
-6 + 8x = 10 + 7x
Solving
-6 + 8x = 10 + 7x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-7x' to each side of the equation.
-6 + 8x + -7x = 10 + 7x + -7x
Combine like terms: 8x + -7x = 1x
-6 + 1x = 10 + 7x + -7x
Combine like terms: 7x + -7x = 0
-6 + 1x = 10 + 0
-6 + 1x = 10
Add '6' to each side of the equation.
-6 + 6 + 1x = 10 + 6
Combine like terms: -6 + 6 = 0
0 + 1x = 10 + 6
1x = 10 + 6
Combine like terms: 10 + 6 = 16
1x = 16
Divide each side by '1'.
x = 16
Simplifying
x = 16
HOPE I HELPED!!! :)