Answer:
3. b. y = ⅝x - ½
4. b. y = ⁵/2x + ½
Step-by-step explanation:
Recall: Slope-intercept form of equation is given as y = mx + b
Where, m = slope, and b = y-intercept.
To find the equation of each line, we must first find the b and m of each graph.
3. Slope of the line using two points on the line, (4, 2) and (-4, -3):
Slope = change in y/change in x = (-3 - 2)/(-4 - 4) = -5/-8 = ⅝
Slope (m) = ⅝
To find y-intercept (b), substitute m = ⅝, and (x, y) = (4, 2) into y = mx + b. Thus:
2 = ⅝(4) + b
2 = ⁵/2 + b
2 - ⁵/2 = b
b = (4 - 5)/2
b = -½
To write the equation, substitute m = ⅝ and b = -½ into y = mx + b
y = ⅝x + (-½)
y = ⅝x - ½
4. Slope of the line using two points on the line, (1, 3) and (-1, -2):
Slope = change in y/change in x = (-2 - 3)/(-1 - 1) = -5/-2 = ⁵/2
Slope (m) = ⁵/2
To find y-intercept (b), substitute m = ⁵/2, and (x, y) = (1, 3) into y = mx + b. Thus:
3 = ⁵/2(1) + b
3 = ⁵/2 + b
3 - ⁵/2 = b
b = ½
b = ½
To write the equation, substitute m = ⁵/2 and b = ½ into y = mx + b
y = ⁵/2x + ½
