Answer:
The length is 7 m
The width is 10 m
Step-by-step explanation:
length = x
width = 2x - 4
length * width = area
It is given that the area is 70 
From there
x * (2x - 4) = 70
- 4x = 70
- 4x - 70 = 0
- 2x - 35 = 0
Now we have a quadratic equation, which is a
+ bx + c = 0, where a
0
In this equation a = 1, b = -2 and c = -35
Discriminant (D) formula is b² - 4ac
D =
- 4 * 1 * (-35) = 144 > 0
This discriminant is more than 0, so there are two possible x
Their formulas are
and
=
= -5 < 0 (the length of the rectangle has to be more than 0, so we don't use this x)
=
= 7 > 0 (this one is right)
Calculating the dimensions
length = x = 7 (m)
width = 2x - 4 = 2 * 7 - 4 = 10 (m)
So hmm check the picture below
the height or altitude is CD
and the base is AB
how long are those? well
Y=mx+b
x=number of newspapers
37.5 earned for 5 newspapers
37.5=5m+b
earned 75 and deliverd 20 newpapers
75=20m+b
we have
37.5=5m+b and
75=20m+b
multiply first equaiton by -1 and add to other equaiton
-37.5=-5m-b
<u>75=20m+b +</u>
37.5=15m+0b
37.5=15m
divide both sides by 15
2.5=m
sub back to find b
75=2.5(20)+b
75=50+b
minsu 50 both sides
25=b
y=2.5x+25 is lnear funtion
Answer:55.73333333333
Step-by-step explanation:
-2 should be distributed to (x-3). so you would get the answer of -2x+6