# Lesson 14 Write and Solve Equations with Unknowns

• Let’s work with equations with unknown numbers.

## Warm-up Number Talk: Fives

Find the value of each expression mentally.

## Activity 1 Card Sort: Unknown Numbers

Your teacher will give you a set of cards. Match each equation with a situation or diagram.

## Activity 2 Write Equations with an Unknown Number

• Write an equation to represent each diagram or situation. Use a symbol for the unknown. Be prepared to share your reasoning.

• Find the number that makes each equation true. Rewrite the equation with the solution.

diagram or situation

equation with symbol

equation with solution

Jada has some packs of sports cards. Each pack has 5 cards. If Jada has 45 cards, how many packs of cards does she have?

The school has 6 bags. Each bag has 10 basketballs in it. How many basketballs does the school have?

## Problem 1

Write an equation for the situation. Use a ? for the unknown. Find the number that makes the equation true.

There are 4 soccer teams. Each soccer team has 10 players. How many players are there altogether?