Answer:
x = 0
, y = 4
Step-by-step explanation:
Solve the following system:
{y = 4 - 3 x | (equation 1)
x + 2 y = 8 | (equation 2)
Express the system in standard form:
{3 x + y = 4 | (equation 1)
x + 2 y = 8 | (equation 2)
Subtract 1/3 × (equation 1) from equation 2:
{3 x + y = 4 | (equation 1)
0 x+(5 y)/3 = 20/3 | (equation 2)
Multiply equation 2 by 3/5:
{3 x + y = 4 | (equation 1)
0 x+y = 4 | (equation 2)
Subtract equation 2 from equation 1:
{3 x+0 y = 0 | (equation 1)
0 x+y = 4 | (equation 2)
Divide equation 1 by 3:
{x+0 y = 0 | (equation 1)
0 x+y = 4 | (equation 2)
Collect results:
Answer: {x = 0
, y = 4
I will give you everything I can do:
11)
Lets say Car A travels at x mph. That means Car B travels at x+2 mph.
Both of them are traveling towards each others, so we can say the total speed is 2x+2.
Now i takes 3 hrs and we know the distance.
Since R*T=D
Then 3(2x+2)=270
So 2x+2=90
2x=88
x=44
12)
To find perpendicular we want to find the opposite reciprocal of the original slope. Therefore the slope is 3/2.
Now we must find the equation of the line with the given variable.
First find b.
5=3/2*4+b
b = -1
So the equation of this line is:
y=3/2x-1
13) All work will be shown below.
6-3(-2-4x)=2(3(x-4)+7)
6+6+12x=2(3x-12+7)
12+12x=2(3x-5)
12+12x=6x-10
6x=-2
x = -1/3
14)
First we must find the amount each train traveled.
The speed of F train(Freight train)=x
The speed of P train(passenger train)=x+6
Their combined speed is 2x+6
It takes 2 hrs to cover 100 miles
So 2(2x+6)=100
2x+6=50
2x=44
x=22
So the freight train covered 44 miles and the passenger train covered 56 miles.
To find average speed you must do Total Distance/Total Time.
44/2 and 56/2
Which are 22 and 28.
The average speed of F train is 22 mph and average speed of P train is 28 mph.
15) Again opposite reciprocal.
3/5 -> -5/3
Work:
-4=-3*-5/3+b
-4=5+b
b=-9
y = -5/3x-9
16)
F=kx-kx0
First kx0 = 0
So F=kx
So x=F/k
Answer:
57.5
Step-by-step explanation:
The constant of proportionality is "k" in the equation ...
y = kx
It can be found from values of x and y using ...
k = y/x
For the given values, it is ...
k = (287.5 mi)/(5 h) = 57.5 mi/h
The constant of proportionality relating miles to hours is 57.5.
Answer:
n = , n =
Step-by-step explanation:
6n² - 5n - 7 = - 8 ( add 8 to both sides )
6n² - 5n + 1 = 0 ← in standard form
Consider the product of the factors of the coefficient of the n² term and the constant term which sum to give the coefficient of the n- term
product = 6 × 1 = 6 and sum = - 5
The factors are - 3 and - 2
Use these factors to split the n- term
6n² - 3n - 2n + 1 = 0 ( factor the first/second and third/fourth terms )
3n(2n - 1) - 1(2n - 1) = 0 ← factor out (2n - 1) from each term
(2n - 1)(3n - 1) = 0 ← in factored form
Equate each factor to zero and solve for n
3n - 1 = 0 ⇒ 3n = 1 ⇒ n =
2n - 1 = 0 ⇒ 2n = 1 ⇒ n =
Distance from point C to point D: same x coordinate, 4-1=3; 3 units
Distance form point D to F: same y coordinate, 5-2=3
Perimeter is the measure of all sides
3+3+3+3=12
Solution: A. 12 units