I would love to use substitution (It is simplier that way I guess)
solve your system of equations.
x+2y=−1;x−y=5
Solve x+2y=−1 for x:
x+2y+−2y=−1+−2y(Add -2y to both sides)
x=−2y−1
Substitute (−2y−1) for x in x−y=5:
x−y=5
−2y−1−y=5
−3y−1=5(Simplify both sides of the equation)
−3y−1+1=5+1(Add 1 to both sides)
−3y=6
−3y/−3 = 6/−3(Divide both sides by -3)
y=−2
Substitute (−2) for y in x=−2y−1:
x=−2y−1
x=(−2)(−2)−1
x=3(Simplify both sides of the equation)
So the answer is (x = 3 and y = -2)
In this question it is already given that a person travels 8 miles in 0.5 hours. This is enough information to get to the required answer. Let us first write down all the information's that are already given in the question.
In 0.5 hours the person covers a distance = 8 miles
Then
In 1 hour the person covers a distance of = 8/0.5 miles
= 16 miles
So the speed of the person in miles per hour = 16/1 miles/hour
= 16 miles per hour
The mid point of DE is (3,-1)
This can be found with Pythagorean Theorem
The length of “a” is 6. The length of “b” is 4.
The length of DE is ≈ 7.21. The midpoint of this value is found at coordinates (3,-1)
-0.3125 is the answer, but you probably have to round
Perform indicated operations on left side
x*x+4x+4x+4*4=9
x^2+4x+4x+16=9 combine like terms on left side
x^2+8x+16=9 subtract 9 from both sides
x^2+8x+7=0 factor
x^2+x+7x+7=0
x(x+1)+7(x+1)=0
(x+7)(x+1)=0
x=-1, -7