Let's solve each problem step by step and explain the process.
---
Part 1: Write each equation in slope-intercept form
Slope-intercept form is:
$$
y = mx + b
$$
where $ m $ is the slope and $ b $ is the y-intercept.
---
####
① $ 2x + 4y = 8 $
We want to solve for $ y $:
$$
4y = -2x + 8
$$
$$
y = \frac{-2x + 8}{4} = -\frac{1}{2}x + 2
$$
✔ Answer: $ y = -\frac{1}{2}x + 2 $
---
####
② $ 4 - 8x = 2y $
Solve for $ y $:
$$
2y = -8x + 4
$$
$$
y = \frac{-8x + 4}{2} = -4x + 2
$$
✔ Answer: $ y = -4x + 2 $
---
####
③ $ -12x + y = 8 $
Solve for $ y $:
$$
y = 12x + 8
$$
✔ Answer: $ y = 12x + 8 $
---
####
④ $ 2y - 6 = -6x $
Add 6 to both sides:
$$
2y = -6x + 6
$$
Divide by 2:
$$
y = -3x + 3
$$
✔ Answer: $ y = -3x + 3 $
---
####
⑤ $ 7 = 2x - y $
Solve for $ y $:
$$
-y = -2x + 7
$$
Multiply both sides by -1:
$$
y = 2x - 7
$$
✔ Answer: $ y = 2x - 7 $
---
####
⑥ $ 4y = 4x $
Divide both sides by 4:
$$
y = x
$$
✔ Answer: $ y = x $
---
Part 2: Write the slope-intercept form given slope and y-intercept
Use: $ y = mx + b $
---
####
⑦ Slope = 3, y-intercept = -2
$$
y = 3x - 2
$$
✔ Answer: $ y = 3x - 2 $
---
####
⑧ Slope = -3, y-intercept = 7
$$
y = -3x + 7
$$
✔ Answer: $ y = -3x + 7 $
---
####
⑨ Slope = 0, y-intercept = -1
A zero slope means a horizontal line:
$$
y = 0x - 1 = -1
$$
✔ Answer: $ y = -1 $
---
####
⑩ Slope = $-\frac{1}{2}$, y-intercept = -2
$$
y = -\frac{1}{2}x - 2
$$
✔ Answer: $ y = -\frac{1}{2}x - 2 $
---
####
⑪ Slope = $-\frac{4}{5}$, y-intercept = 0
$$
y = -\frac{4}{5}x + 0 = -\frac{4}{5}x
$$
✔ Answer: $ y = -\frac{4}{5}x $
---
####
⑫ Slope = -1, y-intercept = -4
$$
y = -x - 4
$$
✔ Answer: $ y = -x - 4 $
---
✔ Final Answers Summary:
| Problem | Answer |
|--------|--------|
| ① | $ y = -\frac{1}{2}x + 2 $ |
| ② | $ y = -4x + 2 $ |
| ③ | $ y = 12x + 8 $ |
| ④ | $ y = -3x + 3 $ |
| ⑤ | $ y = 2x - 7 $ |
| ⑥ | $ y = x $ |
| ⑦ | $ y = 3x - 2 $ |
| ⑧ | $ y = -3x + 7 $ |
| ⑨ | $ y = -1 $ |
| ⑩ | $ y = -\frac{1}{2}x - 2 $ |
| ⑪ | $ y = -\frac{4}{5}x $ |
| ⑫ | $ y = -x - 4 $ |
---
🔍 Explanation of Key Concepts:
-
Slope-intercept form: Always write as $ y = mx + b $
- To convert equations: isolate $ y $ on one side.
- When given slope and y-intercept, plug into $ y = mx + b $
- A slope of 0 gives a horizontal line (constant $ y $)
- A y-intercept of 0 means the line passes through the origin
Let me know if you'd like this formatted as a printable worksheet or need graphs!
Parent Tip: Review the logic above to help your child master the concept of slope intercept form to standard form worksheet.