Answer:
z = x^3 +1
Step-by-step explanation:
Noting the squared term, it makes sense to substitute for that term:
z = x^3 +1
gives ...
16z^2 -22z -3 = 0 . . . . the quadratic you want
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<em>Solutions derived from that substitution</em>
Factoring gives ...
16z^2 -24z +2z -3 = 0
8z(2z -3) +1(2z -3) = 0
(8z +1)(2z -3) = 0
z = -1/8 or 3/2
Then we can find x:
x^3 +1 = -1/8
x^3 = -9/8 . . . . . subtract 1
x = (-1/2)∛9 . . . . . one of the real solutions
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x^3 +1 = 3/2
x^3 = 1/2 = 4/8 . . . . . . subtract 1
x = (1/2)∛4 . . . . . . the other real solution
The complex solutions will be the two complex cube roots of -9/8 and the two complex cube roots of 1/2.
Answer:
Her usual rate is 0.8333 miles per hour.
Step-by-step explanation:
The velocity formula is given by:

In which d is the distance and t is the time.
She completed the first half of the walk 1 mi/h faster than usual
Her usual rate is v. 1mph faster is v + 1.
The second half of the walk 2 mi/h slower than the first half.
The first half is v + 1.
2mph slower is v + 1 - 2 = v - 1. Then
Total rate:
7.2 hours, and 6 miles. So
One half is v+1 and the other is v - 1. This is why each is multiplied by 0.5.



Her usual rate is 0.8333 miles per hour.
Answer:
15
Step-by-step explanation:

Cross multiply to get 25x = 375
Divide each side by 25 to get x = 15
Mutiply straight across 10x