I will solve this problem by determining the slope (m) and y-intercept (b) for each of the six lines shown in the graphs, and then writing the equation in the form $y = mx + b$.
I'll work through each graph one by one.
Graph 1
First, look closely:
- The line passes through the points (0, 3) and (2, 0).
- The y-intercept is clearly at (0, 3), so b = 3.
- To find the slope, I'll use the formula: $m = \frac{y_2 - y_1}{x_2 - x_1}$.
Let me calculate the slope using the points (0, 3) and (2, 0):
$m = \frac{0 - 3}{2 - 0} = \frac{-3}{2} = -1.5$
So, the equation is $y = -1.5x + 3$.
Graph 2
First, look closely:
- The line passes through the points (0, -2) and (2, 2).
- The y-intercept is at (0, -2), so b = -2.
- Using the slope formula with points (0, -2) and (2, 2):
$m = \frac{2 - (-2)}{2 - 0} = \frac{4}{2} = 2$
So, the equation is $y = 2x - 2$.
Graph 3
First, look closely:
- The line passes through the points (0, -1) and (2, -3).
- The y-intercept is at (0, -1), so b = -1.
- Using the slope formula with points (0, -1) and (2, -3):
$m = \frac{-3 - (-1)}{2 - 0} = \frac{-2}{2} = -1$
So, the equation is $y = -x - 1$.
Graph 4
First, look closely:
- The line passes through the points (0, -2) and (1, 2).
- The y-intercept is at (0, -2), so b = -2.
- Using the slope formula with points (0, -2) and (1, 2):
$m = \frac{2 - (-2)}{1 - 0} = \frac{4}{1} = 4$
So, the equation is $y = 4x - 2$.
Graph 5
First, look closely:
- The line passes through the points (0, -4) and (2, -7).
- The y-intercept is at (0, -4), so b = -4.
- Using the slope formula with points (0, -4) and (2, -7):
$m = \frac{-7 - (-4)}{2 - 0} = \frac{-3}{2} = -1.5$
So, the equation is $y = -1.5x - 4$.
Graph 6
First, look closely:
- The line passes through the points (0, 1) and (2, 2).
- The y-intercept is at (0, 1), so b = 1.
- Using the slope formula with points (0, 1) and (2, 2):
$m = \frac{2 - 1}{2 - 0} = \frac{1}{2} = 0.5$
So, the equation is $y = 0.5x + 1$.
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Here are the final answers for each graph:
1.
Slope: -1.5,
y-intercept: 3,
Equation: $y = -1.5x + 3$
2.
Slope: 2,
y-intercept: -2,
Equation: $y = 2x - 2$
3.
Slope: -1,
y-intercept: -1,
Equation: $y = -x - 1$
4.
Slope: 4,
y-intercept: -2,
Equation: $y = 4x - 2$
5.
Slope: -1.5,
y-intercept: -4,
Equation: $y = -1.5x - 4$
6.
Slope: 0.5,
y-intercept: 1,
Equation: $y = 0.5x + 1$
Parent Tip: Review the logic above to help your child master the concept of writing an equation of a line worksheet.