<human>:  Sara’s house is 100 square feet larger than 2 times Nada's house. If Sara's house is 1000 square feet, how many square feet is Nada's house?
<bot>: Define a variable ** Let the number of square feet in Nada's house be y.
Write an equation ** 2y + 100 = 1000.
Simplify ** 2y = 900.
Divide by 2 ** Meaning, y= <<450=450>>450 square feet.
#### 450