Area of a rectangle = l * w
A = Area of a rectangle
l = length
w = width
In our problem,
l = x
w = x - 3
A = 180 square inches
Plug our numbers into the area formula of a rectangle
180 square inches = x(x-3)
Distribute the x into (x-3)
180 square inches = x^2 - 3x
subtract 180 from both sides
0 = x^2 - 3x -180.
Factor the express on the left side of the equation
0 = (x-15) (x+12).
Set each term equal to zero and solve for x
x+12 = 0.
Subtract 12 from both sides
x = -12 <--- lengths of a rectangle cannot be negative, therefore, we need to check the other term we factored.
set x-15 equal to zero
x-15 = 0.
Add 15 to both sides
x = 15.
We know l = x so now we know that the length i = 15 inches.
We also know that the width = length - 3
w = 15 - 3
w = 12
The width is 12 inches and the length is 15 inches
Answer: Adults = 58
Children = 42
Step-by-step explanation:
Let adults be denoted as a
Let Children be denoted as c
a + c = 100 ...... i
10a + 5c = 710 ...... ii
Multiply I by 5
Multiply ii by 1
5a + 5c = 500 ...... iii
10a + 5c = 710 ...... iv
Subtract iii from iv
5a = 210
a = 210/5
a = 42
Since a + c = 100
c = 100 - 42 = 58.
Adults = 58
Children = 42
Answer:
30
Step-by-step explanation:
Students performing in the school concert=40%
let the students in the class be x
hence 40% of the class=12
where 40%=40/100=4/10=2/5 and of means multiplication
(2/5)*x=12
multiplying both sides by 5/2
hence the equation becomes
x=12*5/2
x=60/2
x=30
so the total students in the class are 30
We have been given that a circle of a certain radius has an area which is numerically 5 times the value of the circumference. We are asked to find the radius of the circle.
We know that area of circle with a radius of r units is 
.
We know that circumference of a circle is 
.
5 times the value of circumference would be 
.
Now we will equate 5 times circumference with area as:
Let us solve for r.
Therefore, the radius of the circle would be 10 units.
