It's B. Since the slope is -8/1 x. Slope is rise/run. The other answers doesn't make sense since the x is put in a different place.
Slope-intercept form is y = mx + b, so to turn that equation into slope-intercept you'll need to get y alone
4x - 8y = 8 --- subtract 4x
-8y = 8 - 4x --- divide by -8
y = -1 + (1/2)x --- reorder to match "mx + b"
y = (1/2)x - 1
in y = mx + b, "m" is the slope and "b" is the y-intercept. so for part B, your slope is (1/2) and your y-intercept is (-1). take the sign with you.
for part C, you'll need to know point-slope form: (y - y1) = m(x - x1)
you'll also need to be aware that "perpendicular" lines have a slope that is the opposite reciprocal of the original line.
the original slope is (1/2). change the sign to negative and form a reciprocal: your new slope is -2. plug that into your point-slope form
(y - y1) = m(x - x1)
(y - y1) = (-2)(x - x1)
and lastly, plug in your given point: (1, 2)
y - 2 = (-2)(x - 1)
so, just to look a little neater without all of the work:
A) y = (1/2)x - 1
B) m = (1/2), b = -1
C) y - 2 = (-2)(x - 1)
y = -1.625 sorry if its incorrect, hope it helps tho!
no, this is false. 1 is greater than 12/20.
Answer:
Step-by-step explanation:
- speed = distance / time
- time = distance / speed
a)
i)
<u>Time taken at the first part:</u>
ii)
<u>Time taken at the second part:</u>
- (190 - 105) / (x + 12) =
- 85/(x + 12)
b)
<u>If time is 3 hours and 15 minutes = 3 1/4 hours = 13/4 hours, the equation is:</u>
- 105/x + 85/(x + 12) = 13/4
- 4(x + 12)*105 + 4(85x) = 13x(x + 12)
- 13x² - 604x - 5040 = 0
c)
<u>Solve the equation:</u>
- 13x² - 604x - 5040 = 0
- x = [604 ± √((-604)² + 4*13*5040) ]/26 =
- [604 ± √626896]/26 =
- [604 ± 791.77]/26
- x = (604 + 791.77)/26 = 53.68 km/h (taking positive root only)
d)
- 105/x = 105/53.68 h = 1.956 h = 1 h 0.956*60 min = 1 h 57 min (rounded)
- 85/(53.68 + 12) = 85/65.68 = 1.294 h = 1 h 0.294*60 min = 1 h 18 min (rounded)
