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
5x + y = -13.....multiply by -3
4x + 3y = -17
-----------------
-15x - 3y = 39 (result of multiplying by -3)
4x + 3y = -17
-----------------add
-11x = 22
x = -22/11
x = -2
5x + y = -13
5(-2) + y = -13
-10 + y = -13
y = -13 + 10
y = -3
solution (-2,-3)
The correct answer is –6x + 15 < 10 – 5x.
We can tell this by solving for x.
–3(2x – 5) < 5(2 – x) ----> Multiply to the parenthesis.
-6x + 15 < 10 - 5x ----> This is answer #3 and now we add 5x to both sides
-x + 15 < 10 ----> subtract 15 from both sides
-x < -5 ----> Divide by -1
x > 5 (Note that you have to change the direction of the sign when dividing by a -1. Therefore it does not match answer #1).
Answer:
2/3
Step-by-step explanation:
-5/12 ÷ -5/8
Copy dot flip
-5/12 * -8/5
The 5's cancel
-8/-12
Divide the top and bottom by -4
2/3
Answer:
V
≈
179.59in³
Step-by-step explanation:
