Answer: the speed of the current is 8 mph.
Step-by-step explanation:
Let represent the speed of the current
boat can travel 23mph in still water. This means that the total speed with which the boat travelled is (23 + x) mph.
Time = distance/speed
If it travels 248 miles with the current, it means that the time it took the boat to travel with the current is
248/(23 + x)
in the same length of time it travels 120 miles against the current. This means that the total speed with which the boat travelled is (23 - x) mph. The time it took the boat to travel against the current is
120/(23 - x)
Since the time is the same, it means that
248/(23 + x) = 120/(23 - x)
Cross multiplying, it becomes
248(23 - x) = 120(23 + x)
5704 - 248x = 2760 + 120x
120x + 248x = 5704 - 2760
368x = 2944
x = 2944/368
x = 8 mph
Answer:
not sure how to really answer this question.
.45 is between 0.4 and 0.5
Answer:
Step-by-step explanation:
hello :
5x²+8x-4 quadratic expression when : a = 5 and b=8 and c= -4
∆ = b²-4ac ∆ = 8²-4(5)(-4) = 64 +80 = 144 = 12²
X1 = ( -b -√∆)/2a X1 = (-8-12)/10 = -20/10= -2
X2 =(-b+√∆)/2a X2 = (-8+12)/10 = 4/10 = 2/5
us factorisation : a(X-X1)(X-X2)
5x²+8x-4= 5(x+2)(x-2/5) = (x+2)(5x-2)
you can verify ; (x+2)(5x-2) = 5x²-2x+10x-4 = 5x²+8x-4
The numbers that are irrational are ∛4 and 4 + √5
<h3>How to determine which of the numbers are irrational?</h3>
The numbers are given as:
negative four and 8237 ten thousandths, one half pi, cube root of four, and four plus the square root of twenty-five
Rewrite properly as:
-4.8237, π/2, ∛4 and 4 + √5
When the above numbers are evaluated, we have:
-4.8237 = -4.8237
π/2 = 11/7
∛4 = 1.5874.....
4 + √5 = 6.23606.....
Irrational numbers are numbers that cannot be represented as a fraction of two integers and they are always non-terminating decimals
∛4 and 4 + √5 are non-terminating decimals
Hence, the numbers that are irrational are ∛4 and 4 + √5
Read more about irrational numbers at:
brainly.com/question/8798082
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