Question

d. lin has 5 books about outer space. her teacher gives her some more books. now she has 10 books about outer space. how many books did lin’s teacher give her? show your thinking using drawings, numbers, or words.

Explanation:

Step1: Define unknown variable

Let $x$ = number of books teacher gave.

Step2: Set up equation

$5 + x = 10$

Step3: Solve for $x$

$x = 10 - 5$

Answer:

5