x = number of minutes used, y = total cost in dollars
Plan A: y = 0.09x + 24
Plan B: y = 0.14x + 20
Equate the two right hand side (RHS) expressions and solve for x
0.14x + 20 = 0.09x + 24
0.14x - 0.09x = 24 - 20
0.05x = 4
x = 4/0.05
x = 80
The two plans will cost the same amount of money if you use up 80 minutes
Plug in x = 80 into either equation to find y
y = 0.09*x + 24
y = 0.09*80 + 24
y = 31.20
or
y = 0.14*x + 20
y = 0.14*80 + 20
y = 31.20
So both plans will cost $31.20 if you use up 80 minutes
Answer:
a)
Step-by-step explanation:
is approximately 17.8
17² = 289
18² = 324
315 is between 289 and 324
X⁴ - y⁴
x⁴ - x²y² + x²y² - y⁴
x²(x²) - x²(y²) + y²(x²) - y²(y²)
x²(x² - y²) + y²(x² - y²)
(x² + y²)(x² - y²)
Steve will earn $160 interest after four years ⇒ 1st answer
Step-by-step explanation:
The formula of the simple interest is I = Prt, where
- P is the initial deposit
- r is the annual rate in decimal
- t is the time of investment
∵ Steve opens a bank account with a simple annual interest rate of 5%
∴ r = 5% = 5 ÷ 100 = 0.05
∵ His initial deposit is $800
∵ He will put the money for four years
∴ t = 4
- Substitute all these values in the formula above
∵ I = 800(0.05)(4)
∴ I = 160
Steve will earn $160 interest after four years
Learn more:
You can learn more about the interest in brainly.com/question/13018049
#LearnwithBrainly