The police department uses a formula to determine the
1 answer:
9514 1404 393
Answer:
78.71 mph
Step-by-step explanation:
You're looking for the solution to ...
d = 88
0.0015r^2 +r = 88
0.0015r^2 +r -88 = 0
Using the quadratic formula*, we find ...
r = (-1 +√(1² -4(0.0015)(-88)))/(2×0.0015)
r = (-1 +√1.528)/0.003 = 0.236123/0.003 = 78.7077
The speed of the car was about 78.71 mph.
_____
* The quadratic formula will also give a negative answer of about -745 mph, which is not relevant to the situation.
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Answer:
x = 7
Step-by-step explanation:
See the attached figure.
As shown: A C D F is a trapezoid and BE is a mid-segment.
The mid-segment of the trapezoid is the average of its bases.
BE = 0.5 ( A F + C D)
Given: CD = 18 , BE = 2x + 10 and A F = 6x - 12
So,
2x + 10 = 0.5 ( 18 + 6x - 12)
Solve for x
2x + 10 = 0.5 (6 + 6x)
2x + 10 = 3 + 3x
10 - 3 = 3x - 2x
∴ x = 7
<u>So, the value of x is 7</u>
Answer:
30 cm
Step-by-step explanation: