100 degrees - all angle measurements in a triangle will add up to 180 degrees (45+55 = 100, 180-100 = 80)
Answer:
y=4/5x+1
Step-by-step explanation:
y=mx+b
m = slope = 4/5
b = y-intercept= 1
y=4/5x+1
Answer:
8 days
Step-by-step explanation:
On day 8, Isabella will save 256 nickels, bringing her total to 510.
_____
The number of nickels saved on day n is 2^n. The total is 2^(n+1)-2.
_____
The above can be written down from your knowledge of binary sequences. If you want a more formal development, read on.
__
The number of nickels saved on day n is a geometric sequence with first term 2 and common ratio 2. The n-th term of the sequence is ...
an = a1·r^(n-1) = 2·2^(n-1) = 2^n
The sum of n terms of the sequence is ...
S = a1(r^n -1)/(r -1) = 2(2^n -1)/(2-1)
S = 2^(n+1) -2
__
We want S > 500, so ...
500 < 2^(n+1) -2
502 < 2^(n+1)
251 < 2^n
log(251) < n·log(2)
n > log(251)/log(2)
n > 7.97 . . . . . . . . 8 days or more to save more than 500 nickels
Answer:
Option D.
Step-by-step explanation:
The given inequality is
.
To graph this inequality, we need to graph the corresponding linear equation;

The intercepts are
and
.
Plot these two points and draw a solid straight line through them.
We then test the inequality with the point (0,0).
.
.
This statement is false.
So we shade the lower half plane to obtain the graph in option D.