Yes you are right it's C)
Notice that f(-2) = (-2)³ +2( - 2)² + 4(-2) + 8 =0
Then x³+2x²+4x+8 is divisible by (x+2)
Perform this division & you will get:
x³+2x²+4x+8 = (x+2)(x²+4)
The root of (x+2) is the value that render it nil, that is x=-2
The root of (x²+4) are imaginary (not real) because
x²+4 =0 ==> x² = -4 & x=√-4 or x= 2i (nor real).
Hope you understood the reasoning
Answer:
10 years
Step-by-step explanation:
the average or mean value is the sum of all data points divided by the number of data points.
x = the unknown age of the 5th student.
average = 9 = (5 + 7 + 8 + 15 + x)/5
45 = 5 + 7 + 8 + 15 + x = 35 + x
x = 45 - 35 = 10
the 5th student is 10 years old.
Answer:x>7 or x ≤ -3
Solving the 1st inequality
-6x +14 < -28 --------------- (Collect like terms)
-6x < -28 - 14
-6x < - 42 -------------------- (Divide both sides by -6)
Note: If you decide an inequality expression by a negative value, the inequality sign changes)
-6x/-6 > -42/-6
x > 7
Solving the 2nd inequality
9x + 15 ≤ −12 ----------- (Collect like terms)
9x ≤ −12 - 15
9x ≤ −27 ------------------(Divide both sides by 9)
9
9x/9 ≤ −27/9
x ≤ -3
Bring both results together, we get
x>7 or x ≤ -3
The final result is complex (i.e. can't be combined together).
Step-by-step explanation:
Answer:
here it is
Step-by-step explanation:
Answer:
10
Step-by-step explanation:
125/12.5