60% of the 50 students in Jessie’s gym class are 12 years old. How many students in Jessie’s class are 12 years old?
2 answers:
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Answer:
y = - 3x + 11
Step-by-step explanation:
the altitude is a line from the vertex A drawn perpendicular to the opposite side BC
calculate the slope of BC using the slope formula
m =
with (x₁, y₁ ) = B (- 7, 3 ) and (x₂, y₂ ) = C (- 1, 5 )
=
=
=
=
given a line with slope m then the slope of a line perpendicular to it is
= -
= -
= - 3
the equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept ) , then
y = - 3x + c ← is the partial equation
to find c substitute A (4, - 1 ) into the partial equation
- 1 = - 12 + c ⇒ c = - 1 + 12 = 11
y = - 3x + 11 ← equation of altitude from A
The first thing we are going to do is find the area of the field. To do this we are going to use the area of a square formula: 
Were
is the area in square kilometers
is one of the sides of the square
We know for our problem that the side lengths of the field are 0.9 kilometers, so
. Lets replace that value in our formula to find :
Now, to find the population density of the filed, we are going to use the population density formula:
where
is the population density in <span>in burrows per square kilometer
</span>
is the number of burrows
is the are of the field
We know that
and , so lets replace those values in our formula:
We can conclude that the <span>density of prairie dog burrows is approximately 2444 burrws per square kilometer.</span>
Were
We know for our problem that the side lengths of the field are 0.9 kilometers, so
Now, to find the population density of the filed, we are going to use the population density formula:
where
</span>
We know that
We can conclude that the <span>density of prairie dog burrows is approximately 2444 burrws per square kilometer.</span>