Answer:
car a-50 kilos per hour
car b-55 kilos per hour
car b is faster
Step-by-step explanation:
150/3=50
220/4=55
X = pencils, y = pens
8x + 6y = 8.50
4x + 4y = 5.....multiply by -2
----------------
8x + 6y = 8.50
-8x - 8y = -10 (result of multiplying by -2)
-----------------add
-2y = - 1.50
y = -1.50 / -2
y = 0.75 <=== pens cost 0.75
4x + 4y = 5
4x + 4(0.75) = 5
4x + 3 = 5
4x = 5 - 3
4x = 2
x = 2/4
x = 0.50 <== pencils cost 0.50
6d -11/2 = 2d -13/2
Subtract 2d from both sides
6d -11/2 - 2d = 2d -13/2 - 2d
Simplifying
4d -11/2 = -13/2
Add 11/2 to both sides
4d -11/2 + 11/2 = -13/2 + 11/2
Simplifying
4d = -2/2
4d = -1
Divide both sides by 4
4d/4 = -1/4
Simplifying
d = - 1/4
We're given that 
and 
, and want to find 
.
By the chain rule, we have
and
Then
(because the point 
corresponds to 
)
Answer:
AB = 9/2 cm
AB = 4.5 cm
Step-by-step explanation:
The area of small rectangle
x * (x-4) = x^2 -4x
The area of the big rectangle
The height is 2x +x and the width is x-2
(2x+x) * (x-2)
(3x) * (x-2)
3x^2 -6x
Add the areas together
x^2 -4x + 3x^2 -6x
4x^2 -10x
This is equal to 36
4x^2 -10x=36
Subtract 36 from each side
4x^2 -10x -36=36-36
4x^2 -10x-36=0
Divide each side by 2
2x^2 -5x -18=0
Factor
(x + 2) (2 x - 9) = 0
Using the zero product property
x+2=0 2x-9=0
x = -2 2x =9
x = -2 x = 9/2
Since we cant have a negative length
x = 9/2
AB = 9/2 cm
