Karen's age is 7 years more than 9 times the age of her niece Emma.If the sum of their ages is 57,what is Emma's age?Make and solve an equation.

first represent the unknowns using variables:

let x = age of the Emma
let 9x+7 = age of Karen (according to first statement)
then set-up equation using the given conditions:
x + (9x+7) = 57
combine similar terms,, for terms with the same variable, add the numerical coefficient (number before the variable) and copy the variable:
x + 9x + 7 = 57
10x = 57 - 7
*note: 7 is transposed to other side of equation, and when transposing, the sign becomes the opposite*
10x = 50
x = 5 yrs old (age of Emma)
to get Karen's age, just substitute x = 5 to 9x + 7,,

hope this helps :)