ANSWER
Group A
Step by step explanation
I am bad at explaining things
If we want to find The group with the youngest age , we have to find the mean. The mean , means that we add up all the numbers ( the age) ,then divide them with how much number you added . For example, we add the age of group A 9+10+10+10+10+10+10+10+15+15+15+15+15+15+15+15+17+17+17+17+17+17+17+17+19+19+19+19+19+19=449
Than Count how many people are in group A , group A have 30 people that the number you will be dividing
So 449 divided by 30 is 14.966
That the average
The same go for group B
10+10+10+10+10+10+14+14+14+14+14+18+18+18+18+18+18+25+25+25+25+25+28+28+28+28+29+29+29+29=519
There 30 peoples in group B
519 divided by 30 is 19.7
So the Average of groupB is 19.7
Group a is 14.9 and group B is 19.7
Group A average is smaller than Group B that means ,The average of Group A is younger than Group B so the answer will be group a
Group A is the younger Group then group B
<h3>Answer:</h3>
±12 (two answers)
<h3>Explanation:</h3>
Suppose one root is <em>a</em>. Then the other root will be -3<em>a</em>. The product of the two roots is the ratio of the constant coefficient to the leading coefficient:
(<em>a</em>)(-3<em>a</em>) = -27/4
<em>a</em>² = -27/(4·(-3)) = 9/4
<em>a</em> = ±√(9/4) = ±3/2
Then the other root is
-3<em>a</em> = -3(±3/2) = ±9/2 . . . . . . the roots will have opposite signs
We know the opposite of the sum of these roots will be the ratio of the linear term coefficient to the leading coefficient: b/4, so ...
-(a + (-3a)) = b/4
2a = b/4
b = 8a = 8·(±3/2)
b = ±12
_____
<em>Check</em>
For b = 12, the equation factors as ...
4x² +12x -27 = (2x -3)(2x +9) = 0
It has roots -9/2 and +3/2, the ratio of which is -3.
For b = -12, the equation factors as ...
4x² -12x -27 = (2x +3)(2x -9) = 0
It has roots 9/2 and -3/2, the ratio of which is -3.
