Answer:80%
Step-by-step explanation:
18/90 × 100%
=20%
he got 20% of the questions wrong
100% - 20% =80%
=>he got 80% of the questions correct
Answer:
Apply the distributive property
2x+2(4)=2x+8
Multiply 2 by 4
2x+8=2x+8
Move all terms containing x to the left and subtract 2x
2x+8-2x=8
Combine the opposite terms
2x+8-2x
Subtract 2x from 2x
0+8=8
8=8
All real number
Step-by-step explanation:
Answer: 36 sec
Step-by-step explanation:
Let
x------> distance the kitten runs before being caught by the puppy
Remember that
The speed is equal to divide the distance by the time
v=d/t
solve for t
t=d/v
so
equate the time
x/20=(180+x)/25
25x=20(180+x)
25x=3,600+20x
25x-20x=3,600
x=3,600/5=720 m
t=d/v=720/20=36 sec
or
t=(720+180)/25=900/25=36 sec
We can solve this equation by completing the square. Notice that

and

. Therefore, we can turn

into

. y, in this equation, only has one real solution: 4. So your answer would be (B).
7. a
Given,
Diameter = 16 feet
So, radius = 16 feet/2 = 8 feet
Circumference = 2πr
So, circumference of this circle
= 2πr
= 2 × 3.14 × 8 feet
= 3.14 × 16 feet
= 50.24 feet
b.
Given,
Diameter = 16 feet
So, radius = 16 feet/2 = 8 feet
Area = πr²
So, area of this circle
= 3.14 × (8 feet)²
= 3.14 × 64 feet²
= 200.96 feet²