Answer: 205000
Step-by-step explanation:
There's a really easy way to convert any units to other units.
Right now, we have the fraction (4 miles) / (2 hours).
We want to find a fraction that's exactly equal to that one,
but has the units of (miles/minute) or maybe (feet/minute).
Just take the original fraction, and multiply it by some other
fractions.
Each fraction you multiply it by must have the value of ' 1 ' so
you don't change the value of the original fraction. But it can
have different units, that cancel with other units to eventually
give you the units you want.
(4 miles / 2 hours) times (1 hour / 60 minutes)
The second fraction is equal to ' 1 ', because the top and the bottom
have the same value ... 1 hour is the same thing as 60 minutes.
Multiply the fractions: (4 miles x 1 hour) / (2 hour x 60 minutes)
Now you can cancel 'hour' from the top and the bottom, and you have
(4 miles x 1) / (2 x 60 minutes)
= (4 miles) / (120 minutes)
= (4 / 120) mile/minute = 0.0333... mile / minute .
Let's do it again, go a little farther, and get an answer that
might mean more and feel more like an answer.
(4 miles) / (2 hours) x (5280 feet / mile) x (1 hour / 60 minutes)
The 2nd and 3rd fractions both have the value of ' 1 ', because
the top is equal to the bottom.
Multiply all three fractions:
(4 miles x 5280 feet x 1 hour) / (2 hours x 1 mile x 60 minutes)
You can cancel both 'mile' and 'hour' out of the top and bottom,
and look what you have left:
(4 x 5280 feet x 1) / (2 x 1 x 60 minutes)
= (4 x 5280) / (2 x 60) feet / minutes
= (21,120 / 120) feet/minute = 176 feet per minute
Answer:
In a quadratic equation of the shape:
y = a*x^2 + b*x + c
we hate that the discriminant is equal to:
D = b^2 - 4*a*c
This thing appears in the Bhaskara's formula for the roots of the quadratic equation:

You can see that the determinant is inside a square root, this means that if D is smaller than zero we will have imaginary roots (the graph never touches the x-axis)
If D = 0, the square root term dissapear, and this implies that both roots of the equation are the same, this means that the graph touches the x axis in only one point, wich coincides with the minimum/maximum of the graph)
If D > 0 we have two different roots, so the graph touches the x-axis in two different points.
The number is 125 and the equation is 0.8x = 100
Step-by-step explanation:
80% of x is equal to 100.
Write an equation that shows the relationship of 80%, x, and 100
80% = 0.8
0.8x = 100
x = 100/0.8
x = 125
The number is 125 and the equation is 0.8x = 100