Problem of the Week
Did you figure it out? Answer: 40 seconds Solution: By the time the robot starts running, K9 has already gone 20 × 10 = 200 meters. So, we need to know when the distan..
Answer: x = 0
Solution: To solve for x, we need to know the slope of Line B. Line A and Line B are perpendicular, so the slope of Line B is the opposite of the reciprocal of the slope of Line A. Line A’s slope is (y2 – y1) ÷ (x2 – x1) = (3 – 1) ÷ (6 – 2) = 1/2 , so the slope of Line B must be –2. Now that we have a point on the line and its slope, we can write an equation in slope-intercept form:
y = –2x + b
y = 1 x = 2
1 = –4 + b
b = 5
y = –2x + 5
5 is the y–intercept. When y = 5, then x = 0.
Answer: 7:39 am
Solution: Eight minutes, 8 times is 8 × 8 = 64 minutes. There are 60 minutes in an hour, so Evelyn jogs for 1 hour and 4 minutes because 64 minutes – 60 minutes (1 hour) = 4 minutes. One hour after 6:35 am is 7:35 am, and 4 minutes after that is 7:39 am.