So basically
D=RT
distance=rate times time
D=233
carlos speed=55
maria speed=50
total time=4.4 hours
so therefor we have to represent
carlos time
maria time
carlos distance
maria dstance
let's say that
remember that whatever carlost drove is 233 minus maria (time and distance)
and since we are solving for maria time and distnace, solve in terms of them
maria time=t
maria distance=d
carlos time=4.4-t
carlos distance=233-d
remember total D=RT
find their seperate equations
carlos
233-d=55(4.4-t)
maria
d=50(t)
use them to solve
233-d=55(4.4-t)
subsitute 50(t) for d
233-50t=55(4.4-t)
add 50t to both sides
233=55(4.4-t)+50t
distribute using distributiver protperty (a(b+c)=ab+ac)
55(4.4-t)=242-55t
233=242-55t+50t
add like terms
233=242-5t
add 5t to both sides
233+5t=242
subtract 233 from both sides
5t=9
divdie both sides by 5
t=1.8
maria drove 1.8 hours
the answer is A
Answer:
- 0.8
Step-by-step explanation:
The first thing we want to do here is simplify the expression -
( 2x + 5 ) - 2x, Distribute the " " to elements within the parenthesis
= 
2x + 5 - 2x, Focus on simplifying the expression " 2x + 5 "
= 
- 2x
= 
- 2x, Combine fractions
= 
+ 3
= 
x + 3
So we have our simplified expression " x + 3, " with being the coefficient of x. Our requirements are that this fraction should be expressed as a decimal, so we can simply divide the numerator by the denominator to figure that out,
- 4 / 5 = - 0.8,
Solution = - 0.8
It's the first one because the other three go pasted -6 which would make the problem not true.
Answer:
see below
Step-by-step explanation:
The formula for the sum of an infinite geometric series with first term a1 and common ratio r (where |r| < 1) is ...
sum = a1/(1 -r)
Applying this to the given series, we get ...
a. sum = 5/(1 -3/4) = 5/(1/4) = 20
b. sum = d/(1 -1/t) = d/((t-1)/t) = dt/(t-1)
_____
The derivation of the above formula is in most texts on sequences and series. In general, you write an expression for the difference of the sum (S) and the product r·S. You find all terms of the series cancel except the first and last, and the last goes to zero in the limit, because r^∞ → 0 for |r| < 1. Hence you get ...
S -rS = a1
S = a1/(1 -r)
2.66
i need to write 20 characters so im typing this
