Answer:
2 1/3 hours or 2 hours 20 minutes.
51.4 mph to 1 decimal place.
Step-by-step explanation:
Time = distance speed
First 50 miles time taken = 50 / 60 = 5/6 hours
Second 50 miles - time = 50/40 = 5/4 hours.
Final 20 miles - time taken = 20 / 80 = 1/4 hours.
Total time taken = 5/6 + 5/4 + 1/4
= 5/6 + 6/4
= 10/12 + 18/12
= 28/12
= 7/3 or 2 1/3 hours or 2 hours 20 minutes.
Average speed = total distance / total time
= 120 / 7/3
= 120 * 3/7
= 51.4 mph to 1 decimal place.
Answer:
(-2, 3).
Step-by-step explanation:
x + 3y = 7
2x + 4y = 8
1 . x = 7 - 3y.
2. 2(7 - 3y) + 4y = 8
3. 14 - 6y + 4y = 8
-2y = -6
y = 3
4. Substitute y in the second equation:
2x + 4(3) = 8
2x = -14
x = -2..
Answer:
x - intercept: (-22, 0)
y - intercept: (0, 11)
Step-by-step explanation:
Given the linear equation
-3x + 11y = 66
<em><u>Determining the x-intercept</u></em>
We know that the x-intercept can be computed by setting the value y=0 and solving for x.
substitute y = 0
-3x + 11y = 66
-3x + 11(0) = 66
-3x + 0 = 66
-3x = 66
Divide both sides by -3
-3x/-3 = 66/-3
x = -22
Thus, the ordered pair representing the x-intercept : (-22, 0)
<em><u>Determining the y-intercept</u></em>
We know that the y-intercept can be computed by setting the value x=0 and solving for y.
substitute x = 0
-3x + 11y = 66
-3(0) + 11y = 66
0 + 11y = 66
11y = 66
Divide both sides by 11
11y/11 = 66/6
y = 11
Thus, the ordered pair representing the y-intercept : (0, 11)
Therefore, we conclude that:
x - intercept: (-22, 0)
y - intercept: (0, 11)