Identify the Correct Equation from a Graph of a Linear Function

Linear Functions with Graph Interpretation

Which of the following equations corresponds to the function represented in the graph?

–8–8–8–7–7–7–6–6–6–5–5–5–4–4–4–3–3–3–2–2–2–1–1–1111222333444555666777888–3–3–3–2–2–2–1–1–1111222333444555666000

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step video solution

Watch the teacher solve the problem with clear explanations
00:00 Find the appropriate equation for the function in the table
00:03 We want to find the slope of the graph
00:07 We'll take 2 points on the graph
00:13 We'll use the formula to find the function's graph slope
00:16 We'll substitute appropriate values according to the given data and solve for the slope
00:24 This is the graph's slope
00:29 We'll use the linear equation
00:34 We'll substitute appropriate values and solve for B
00:41 This is the value of B (intersection point with Y-axis)
00:52 We'll construct the linear equation using the values we found
00:56 And this is the solution to the question

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

Which of the following equations corresponds to the function represented in the graph?

–8–8–8–7–7–7–6–6–6–5–5–5–4–4–4–3–3–3–2–2–2–1–1–1111222333444555666777888–3–3–3–2–2–2–1–1–1111222333444555666000

2

Step-by-step solution

To solve this problem, we'll follow these steps:

  • Step 1: Identify the slope (m m ) of the line from the graph.
  • Step 2: Determine the y-intercept (b b ) from the graph.
  • Step 3: Match the slope and y-intercept to one of the given equations.

Now, let's work through each step:
Step 1: By observing the graph, we determine the slope (m m ). The line appears to pass through the points (0,4)(0, 4) and (1,5)(1, 5). Calculating the slope m m using the points, m=5410=1 m = \frac{5 - 4}{1 - 0} = 1 .

Step 2: The y-intercept b b is the point where the line crosses the y-axis, which is at (0,4)(0, 4). Therefore, b=4 b = 4 .

Step 3: Using the slope-intercept form y=mx+b y = mx + b , substitute m=1 m = 1 and b=4 b = 4 to get y=1x+4 y = 1x + 4 , which simplifies to y=x+4 y = x + 4 .

Therefore, the solution to the problem is y=x+4 y = x + 4 .

From the given choices, the correct answer is choice 4: y=x+4 y = x + 4 .

3

Final Answer

y=x+4 y=x+4

Key Points to Remember

Essential concepts to master this topic
  • Slope Formula: Use rise over run between two clear points
  • Technique: Find slope: m=5410=1 m = \frac{5-4}{1-0} = 1
  • Check: Verify y-intercept at x=0 gives point (0,4) ✓

Common Mistakes

Avoid these frequent errors
  • Confusing x-intercept with y-intercept
    Don't read the y-intercept as where the line crosses the x-axis = wrong starting point! The x-intercept is where y=0, but y-intercept is where x=0. Always identify the y-intercept as the point where the line crosses the vertical y-axis.

Practice Quiz

Test your knowledge with interactive questions

Determine whether the following table represents a constant function:

XY02468-3-3-3-3-3

FAQ

Everything you need to know about this question

How do I find the slope when the line looks steep?

+

Choose two clear grid points the line passes through. Count the vertical change (rise) and horizontal change (run). Even steep lines follow slope = rise/run.

What if the line doesn't pass exactly through grid intersections?

+

Look for points where the line clearly crosses grid lines. From this graph, (0,4) and (1,5) are obvious intersection points you can use confidently.

Why can't I just guess and check the equations?

+

Guessing wastes time and doesn't teach you the method! Finding slope and y-intercept systematically works for every linear function and builds your understanding.

How do I know which point is the y-intercept?

+

The y-intercept is always where x = 0. Look at the vertical y-axis and see where the line crosses it. In this graph, that's clearly at point (0,4).

What does the slope tell me about the line?

+

Slope = 1 means the line goes up 1 unit vertically for every 1 unit horizontally. It's a 45-degree angle going upward from left to right.

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Functions questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime

More Questions

Click on any question to see the complete solution with step-by-step explanations