Question

mary is x years old. it is her birthday today. her sister, sherry is 4 years older than she is. after 7 years their combined age will be 24 years write a liner=ar equation for their combined age after 7 years

Answer 1

mary is now --- x
sherry is now --- x+4

7 years from now:
mary --- x+7
sherry --- x=4 + 7 = x+11

x+7 + x+11 = 24

I will let you solve it

Answer 2

x=4