Answer: the ordered pair is (-14,-6)
Step by step:
x – 2y = -2 (Eq. 1)
x – 4y = 10 (Eq. 2)
Isolate x in Eq. 2:
x = -2 + 2y
Substitute that solution x in Eq. 2:
x - 4y = 10
-2 + 2y - 4y = 10
Solve for y:
-2 - 2y = 10
-2y = 10 + 2 = 12
y = -6
Then calculate value for x using the above value for y
x = -2 + 2y
x = -2 + 2(-6) = -14
The solution is (x,y)=(-14,-6)
Answer:
t = 3 hours, therefore it cannot be 4 hours
Step-by-step explanation:
Divide the miles traveled by the rate you traveled. This will find the time it took to travel.
180/60 = 3
You drove 3 hours to travel 180 miles, therefore t cannot equal 4.
8/20=y/25
(0.4=y/25)*25
Y= 10
__________
8/20=(x+4)/15
0.4*15=x+4
6=x+4
X=2
9514 1404 393
Answer:
21x² +20x +100 = 0
Step-by-step explanation:
We know the sum of the roots of x² +bx +c = 0 is -b, and their product is c. If the roots are α and β, then ...
The sum of the roots of the new equation will be ...
-b' = (α+1/β)+(β+1/α) = (α+β) +(1/α +1/β) = (α+β)(1 +1/(αβ))
The product of the roots of the new equation will be ...
c' = (α+1/β)(β+1/α) = αβ +2 +1/(αβ)
Using the above relations for (α+β) and αβ, we find that ...
-b' = (-b)(1 +1/c)
c' = c + 2 + 1/c
For the given equation, our definition of b and c is ...
b = 2/3
c = 7/3
so the new equation has values ...
b' = (2/3)(1 + 1/(7/3) = (2/3)(10/7) = 20/21
c' = 7/3 + 2 + 1/(7/3) = 13/3 + 3/7 = 100/21
So, the equation with the roots of interest is ...
x² +20/21x +100/21 = 0
Multiplying by 21 gives ...
21x² +20x +100 = 0