Answer:
D
Step-by-step explanation:
Looking at 49 and 21, you immediately know that 7 can be divided out of both.
49:21
=49/7:21/7
=7:3
7:3 is the answer.
Hope this helps!
Answer:
Morning's average rate = 50 mph, and Afternoon's average rate = 25 mph.
Step-by-step explanation:
Suppose he drove 150 miles for X hours, then his average rate in the morning was (150/X) mph.
Given that he spent 5 hours in driving.
And he drove 50 miles for (5-X) hours, then his average rate in the afternoon was 50/(5-X) mph.
Given that his average rate in the morning was twice his average rate in the afternoon.
(150/x) = 2 * 50/(5-x)
150/x = 100/(5-x)
Cross multiplying terms, we get:-
150*(5-x) = 100*x
750 - 150x = 100x
750 = 100x + 150x
750 = 250x
x = 750/250 = 3.
It means he spent 3 hours in the morning and 2 hours in the afternoon.
So morning's average rate = 150/3 = 50 mph.
and afternoon's average rate = 50/(5-3) = 25 mph.
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Answer:
(c) P(x) = x^4 +3x^3 -10x^2 -30x
Step-by-step explanation:
If the polynomial has integer coefficients, its complex or radical roots come in conjugate pairs. That is, -√10 is also a root. The four roots mean the polynomial has degree 4. That eliminates all but answer choice C.
Each root 'a' gives rise to a factor (x -a), so the factored polynomial is ...
P(x) = (x -0)(x -(-3))(x -√10)(x -(-√10))
P(x) = x(x +3)(x² -10) = x(x³ +3x² -10x -10)
P(x) = x^4 +3x^3 -10x^2 -10x
