Answer:
The speed of the first car is 60 mph
Step-by-step explanation:
speed = distance/time
Solve the above equation for distance to get
distance = speed * time
or simply
d = st
Now we use this formula for distance to write an equation for each car.
Let s = speed of second car
Then since the speed of the first car is 10 mph faster, the first car's speed is s + 10.
The time the two cars traveled is equal but unknown, so let the time = t.
First car: speed = s + 10; time = t; distance = 120 miles
d = st
120 = (s + 10)t
(s + 10)t = 120 Equation 1
Second car: speed = s; time = t; 100 miles
d = st
100 = st
st = 100 Equation 2
Equations 1 and 2 form a system of 2 equations in 2 unknowns.
(s + 10)t = 120
st = 100
Distribute t in the first equation.
st + 10t = 120
From the second equation we know st = 100, so substitute 100 for st.
100 + 10t = 120
10t = 120
t = 2
The time traveled was 2 hours.
Equation 2:
st = 100
Substitute t with 2.
s * 2 = 100
s = 50
The speed of the second car was 50 mph.
The speed of the first car is s + 10.
s + 10 = 50 + 10 = 60
Answer: The speed of the first car is 60 mph
Answer:
Part A
Martha is incorrect because she will pay 1/4 of the cost.
40%+0.35
0.40+0.35
0.75
0.25=25/100=1/4
Part B
Renee-$340
Susan-$297.50
Martha-$212.50
Answer: 8 : 6
Step-by-step explanation:
Answer:
He got 400 coins because there are 100 cents in a dollar. 100*20=2000. 2000/5=400!
Step-by-step explanation:
I hope this helps! Have a great rest of your day!
The equation of the line containing (- 4,5) and perpendicular to the line 5x - 3y = 4 is y = -3 / 5 x + 13 / 5
<h3>How to find the equation of a line?</h3>
The equation of a line can be represented as follows:
y = mx + b
where
Therefore, the equation passes through (-4, 5) and perpendicular to 5x - 3y = 4
Hence,
perpendicular lines follows the rule below:
m₁m₂ = -1
Hence,
5x - 3y = 4
5x - 4 = 3y
y = 5/ 3 x - 4 / 3
m₁ = 5 / 3
5/3 m₂ = -1
m₂ = - 3 / 5
Hence,
using (-4, 5)
5 = - 3 / 5 (-4) + b
5 = 12 / 5 + b
b = 5 - 12 / 5 = 25 - 12 /5 = 13 / 5
Therefore,
y = -3 / 5 x + 13 / 5
learn more on equation of a line here: brainly.com/question/10727767
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