Answer:
The change in the car's distance is 8 feet
Step-by-step explanation:
* Lets explain how to solve the problem
- A car is driving away from a crosswalk
- The distance d (in feet) of the car from the crosswalk t seconds
since the car started moving is given by the formula d = t² + 3.5
- The time increasing from 1 second to 3 seconds
- We need to now the change of the car's distance from the crosswalk
∵ The equation of the distance is d = t² + 3.5
∵ The time is 1 second
∴ d = (1)² + 3.5
∴ d = 1 + 3.5 = 4.5 feet
∵ The time is 3 seconds
∴ d = (3)² + 3.5
∴ d = 9 + 3.5 = 12.5 feet
∵ The change of the distance = d of 3 sec - d of 1 sec
∵ d of 3 sec = 12.5 feet
∵ d of 1 sec = 4.5 feet
∴ The change of the distance = 12.5 - 4.5 = 8 feet
∴ The change in the car's distance is 8 feet
Answer:Store A
Step-by-step explanation:
Given
Store A sells 3 cells phones that cost $165 each and offer 4 th one free
i.e. Effective cost of each cell phone is 
Store B sells each cell phone at 
each
clearly, store A provides a better deal than B because the cost of 4 cell phones is less for Store A i.e.
Answer: 1 9/15
Step-by-step explanation:
Answer:
x = 8
Step-by-step explanation:
Δ TSU and Δ TRV are similar , thus the ratios of corresponding sides are equal, that is
= 
, substitute values
= 
= 
( cross- multiply )
3x = x + 16 ( subtract x from both sides )
2x = 16 ( divide both sides by 2 )
x = 8
Answer:
Step-by-step explanation:
Rewrite this equation in standard quadratic form: x^2 + 13x + 4 = 0.
Here the coefficients are 1, 13 and 4, so the discriminant is
b^2-4ac, or 169 - 4(1)(4) = 153
Since the discriminant is + there are two real, unequal roots. They are:
-13 ± √153
x = ------------------
2
x = ----------------
