Answers:
1. The n-intercept is 12. That means after 12 visits the amount of money on the gift car is $0.
2. The A(n)-intercept is 150. Before the visits, the amount of money on the gift car is $150.
Solution:
Amount of money on the gift card after n number of visits: A(n)=$150-$12.50 n
A(n)=150-12.50 n
1. n-intercept
A(n)=0→150-12.50 n =0
Solving for n: Subtracting 150 both sides of the equation:
150-12.50 n-150 = 0-150
-12.50 n = -150
Dividing both sides of the equation by -12.50:
(-12.50 n) / (-12.50) = (-150) / (-12.50)
n=12
The n-intercept is n=12; for n=12→A(12)=0. Point (n, A(n))=(12,0)
2. A(n) intercept
n=0→A(0)=150-12.50 (0)
A(0)=150-0
A(0)=150
The A(n) intercept is 150; for n=0→A(0)=150. Point (n, A(n))=(0,150)
To write the equation of a line I need slope and y intercept (0,y)
I have y intercept (0,7) of +7 as written in the equation
The equation y=-5/4x + 11/4 has a slope of -5/4
To get perpendicular slope is negated reciprocal
so take -5/4 and flip it -4/5 and change the sign (in this case negative to positive) 4/5
so the new equation is y=4/5x +7 (third one)
The answer is 112 on the number line
