Answer:
1. 15
2. 8
Step-by-step explanation:
The two sequence are geometric progression GP, because they follow a constant multiple (common ratio)
The nth term of a GP is;
Tn = ar^(n-1)
Where;
a = first term
r = common ratio
For the first sequence;
The common ratio r is
r = T3/T2 = 540/90 = 6
r = 6
T2 = ar^(2-1) = ar
T2 = 90 = ar
Substituting the values of r;
90 = a × 6
a = 90/6
a = 15
First term = 15
2. The sam method applies here.
Common ratio r = T3/T2 = 128/32 = 4
r = 4
T2 = ar^(2-1) = ar
T2 = 32 = ar
Substituting the values of r;
32 = a × 4
a = 32/4
a = 8
First term = 8
The dog ran across the yard and barked :)
Answer:
7
Step-by-step explanation:
Try taking everything besides the x away. So the opposite of positive 7 is negative seven on the opposite side. 21-7 is 14 and 2x=14 is all that remains. The opposite of 2 times x is 2 divided by x and since we want to keep the x we divide the 2 on the other side, 14/2 is 7. x=7 is what remains.
The area of the wetland that will be covered in purple loosestrife 7 years from now is modeled by this expression.
500(1.2)^7
After evaluating the expression, the model predicts that approximately 1,792 acres of the wetland will be covered in purple loosestrife 7 years from now. This is not a valid prediction because the total area of the wetland is only 1,240 acres. So a constraint on the model is that the value of the expression 500(1.2)^t must be less than or equal to 1,240.