A geometric sequence is a sequence in which there is a common ratio between any two consecutive terms. In this case if X:Y:Z are in the ratio of 2:7:8 the multiplying by a constant k, we have X=2k, Y= 7k and Z=8k. Then if X, Y-12, Z form a Geometric sequence, it means X/Y-12=Y-12/Z which is the same as 2k/7k-12=7k-12/8k if we cross multply, we get 16k²= 49k²-168k +144 33k²-168k+144 =0 solving for k k = 4 or 1.091 if we take the whole number to find the values of X,Y and z, X= 8, Y= 28 and Z=32
The system of equations for eq 1 which is 3x + y = 118 represents the Green High School which filled three buses(with a specific number of students identified as x) and a van(with a specific number of students identified as y) with a total of 118 students.
for eq 2; 4x + 2y = 164; represents Belle High School which filled four buses(with a specific number of students identified as x) and two vans(with a specific number of students identified as y) with a total of 164 students.
The solution represents the specific number of students in the buses and vans in eq1 and eq 2 with x being 36 students and y being 10 students.
substituting 36 for x and 10 for y in eq 1;
3(36) + 10 = 108 + 10 = 118 total students for Green High School
substituting 36 for x and 10 for y in eq2;
4(36) + 2(10) = 144 + 20 = 164 total students for Belle High school
