Respuesta :
Answer:
B, C, and D.
Step-by-step explanation:
Let's go through each answer choice.
A: To find the slope of a line from two points, we use this formula: [tex](y_2-y_1)/(x_2-x_1)[/tex]. Plugging in the values (-2,0) and (2, -4), we get:
- [tex](-4-0)/(2+2)[/tex]
- [tex]-4/4[/tex]
- [tex]-1[/tex]
Because option A says the slope is 1, but we got -1, option A is false.
B: To find the y-intercept, we use this formula: [tex]b = y_1 - m * x_1[/tex]
- [tex]b = 0 -(-1) * (-2)[/tex]
- [tex]b = 1 * (-2)[/tex]
- [tex]b = -2[/tex]
Since we know the value of b is the y-intercept, we could write the y-intercept as (0,-2). Therefore, option B is true.
C: The equation of a line (in slope-intercept form) is y = mx + b, where y - y-coordinate, m = slope, x = x-coordinate, and b = y-intercept. Since we already solved for the y-intercept and slope, let's plug in those values:
- [tex]y = mx +b[/tex]
- [tex]y = -x -2[/tex]
As you can see, the equation we got here matches the one in option C, meaning it's true.
D: We know that a point is written like this: (x, y). If the x-coordinate is not zero but the y-coordinate is, then it's the x-intercept. Since the question says that (-2,0) is one of the points the line passes through, and option D says that the x-intercept is (-2,0), it's true.
Answer: B, C, D
A is not True:
m = (y2 - y1) / (x2 - x1); Slope Formula
m = (-4 - 0) / (2 - (-2)); Plug in Values & Subtract
m = -4 / 4
m = - 1
m does NOT equal 1, so A is FALSE
B is True:
y = mx + b; Y-intercept Form equation
Choose one of the two coords and place in value for the equation— I chose (2, -4). m is the slope, which we know from solving A
-4 = -1(2) + b; multiply
-4 = -2 + b; add 2 both side
-2 = b
b is y-intercept or where the line hits the y-axis when x is 0– (0, -2), so B is TRUE
C is True:
y = mx + b; Place in Values for m (slope) and b (y intercept)
y = -1x - 2 or y = -x-2; so C is TRUE
D is True:
To find x intercept, set y to 0 and solve for x
y = mx + b
0 = -1(x) -2; multiply -1 & x; add 2 both side
2 = -x; divide both side by -1
-2 = x
This means when y is 0, x is at -2
(-2, 0); so D is TRUE
A is not True:
m = (y2 - y1) / (x2 - x1); Slope Formula
m = (-4 - 0) / (2 - (-2)); Plug in Values & Subtract
m = -4 / 4
m = - 1
m does NOT equal 1, so A is FALSE
B is True:
y = mx + b; Y-intercept Form equation
Choose one of the two coords and place in value for the equation— I chose (2, -4). m is the slope, which we know from solving A
-4 = -1(2) + b; multiply
-4 = -2 + b; add 2 both side
-2 = b
b is y-intercept or where the line hits the y-axis when x is 0– (0, -2), so B is TRUE
C is True:
y = mx + b; Place in Values for m (slope) and b (y intercept)
y = -1x - 2 or y = -x-2; so C is TRUE
D is True:
To find x intercept, set y to 0 and solve for x
y = mx + b
0 = -1(x) -2; multiply -1 & x; add 2 both side
2 = -x; divide both side by -1
-2 = x
This means when y is 0, x is at -2
(-2, 0); so D is TRUE