The quadratic formula is =(-b+-sqrt(b^2-4ac))/2a
as you notice the term under the square root is b^2-4ac if it is postive then the equation clearly will have two real soultions if it is negative then the equation will have two imaginary soultion if it is zero then the the equation will have one soultion
so let us calculate b^2-4ac for our given equation
x^2=4x-5 so let us write it in general form which is ax^2+bx+c=0
subtracting 4x from both sides
x^2-4x=-5
adding 5 to both sides
x^2-4x+5=0
a=1,b=-4,c=5
b^2-4ac=(-4)^2-4(1)(5)=16-20=-4
which means the equation has two imaginary soultions
The area equation here is:

That means that the area depends on the width measurement of the rectangle.
To graph a quadratic function you have to see if the parabole is positive and the transformations, in this case, are positive and have a multiplication by two, which means that the graphics in x=1 and x=-1 will be y=2
Finally, you can conclude that there, you have a relationship between the area and the width of the rectangle because is a quadratic relationship and the area will increase in a quadratic form according to the increase of the width.
Answer:
9a + 6b and 5c - 3d
Step-by-step explanation:
(a)
4a + 7b + 5a - b ← collect like terms
= (4a + 5a) + (7b - b)
= 9a + 6b
(b)
6c + 4d - c - 7d ← collect like terms
= (6c - c) + (4d - 7d)
= 5c - 3d
In the first one it would be (21-8)-6=7.
and in the second one it would be 21-(8-6)=19