Let the middle child be x
youngest child = x - 1
Oldest child = x + 1
(x - 1)^2 = 8(x + 1) + 4
x^2 - 2x + 1 = 8x + 8 + 4
x^2 - 10x - 11 = 0
(x - 11) * (x + 1) = 0
X = - 1 makes no sense. How can a middle child be - 1 years old?
x = 11
The youngest child is 10
The middle child is 11
The oldest child is 12
Check
=====
10^2 = 100
(8*12) + 4
96 + 4 = 100 So the results have been checked.
Let k and d be the Kevin's age and the Daniel's age;
We have the equation:
k = 3 + d;
k - 2 = 4( d - 2 );
We have 3 + d - 2 = 4d - 8;
Then, d + 1 = 4d - 8;
9 = 3d;
d = 3.
Finally, k = 6 years.
Answer:
The horizontal line test may be used to determine whether a function is one-to-one.
The vertical line test may be used to determine whether a relation is a function.
Step-by-step explanation:
