# Linear Equations with 'Graphs of the Galaxy'

**MATHEMATICS SKILL COVERED**

Age 12-13

Plotting linear equations:

- Straight lines not through the origin, any gradient
- Straight lines not through the origin, integer gradients
- Straight lines through the origin, any gradient
- Straight lines through the origin, integer gradients

**HOW TO PLAY**

Use your skills to plot a linear graph that matches the line to destroy space debris. Change the gradient and y-intercept to correctly position the missile, before firing towards the space debris.

- Click on the gradient in the equation, and change it using the dial.
- Click on the y-intercept, and move the slider up or down to change the value
- Once you're happy with the positioning of the line, click FIRE

You have two attempts the answer the question. After this, it is auto-corrected, and another question is revealed.

**SCORING INFORMATION**

For each level, reach the in-game goal and beat the target score to earn a medal (**B**ronze, **S**ilver, **G**old)

**In-game goal: Answer 1 Medium question in the first attempt >>>****Target score****>>>**135-294 points (**B**)**In-game goal: Answer 1 Hard question in the first attempt >>>****Target score****>>>**295-509 points (**S**)**In-game goal: Answer 3 Hard questions in the first attempt >>>****Target score****>>>**1800+ points (**G**)

**Scoring calculation**

The score is calculated as follows:

BASE SCORE: Players have 2 attempts to answer a question, otherwise it is auto-corrected. Players gain double the amount of points for answering the question correctly on the first attempt compared to their second.

- Answered correctly in first attempt - 10 points
- Answered correctly in second attempt - 5 points
- Incorrect (auto-corrected) - 0 point

DIFFICULTY: There are 3 difficulties per level.

- Players start on easy and move up to medium then hard.
- Correctly answer 2 questions in a row on your first attempt to go up a difficulty
- Get 2 incorrect in a row to go down

BONUSES: There are 2 different bonuses that can be obtained in the game, Speedy bonus and Medal bonus.

- Speedy bonus: 3 extra points for answering the question within 20 seconds
- Medal bonus: