Answer:
The radius is 5 cm
Step-by-step explanation:
The formula for the area of a circle is : 
To work out the length of the radius you would first need to divide the area of 78.5 cm by pi (pi=3.14), this gives you 
. This is because by dividing the area by pi we are isolating the value of the radius squared.
The final step is to work out the radius. You can do this by finding the square root of the radius squared which is 25, this gives you 5 cm. This means that the radius is 5 cm. This is because the square root is a number that when squared equals that number.
1) Divide 78.5 by pi.
2) Find the square root of 25 cm squared.
In this question pi is 3.14
So basically you want to isolate only one of the variable on one side so
y=-9+x^2
add 9 to both sides
y+9=x^2
square root both sides
x=
Answer:
Jane got on 16 rides
Step-by-step explanation:
r= numbers of rides
25 + 2r
25 + 2r = 57
-25 -25
_____________
2r\2 32/2
r=16
Answer:
Dotted linear inequality shaded above passes through (0, 4) and (4, 0). Solid exponential inequality shaded below passes through (negative 2,2) & (0,5)
Step-by-step explanation:
we have
----> inequality A
The solution of the inequality A is the shaded area above the dotted line 
The dotted line passes through the points (0,4) and (4,0) (y and x-intercepts)
and
-----> inequality B
The solution of the inequality B is the shaded area above the solid line 
The solid line passes through the points (0,5) and (-2,2)
therefore
The solution of the system of inequalities is the shaded area between the dotted line and the solid line
see the attached figure
Dotted linear inequality shaded above passes through (0, 4) and (4, 0). Solid exponential inequality shaded below passes through (negative 2,2) & (0,5)
For 20% out of 100% it would be 1/5 as you need 5 20s for 100
